Jump to content

Decision Review System

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Darththorn (talk | contribs) at 13:51, 28 December 2023 (Updated for the review limit being no longer a temporary measure.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Decision Review System
Ball tracking visualisation in 2020.
AbbreviationDRS
StatusActive
Year started2008
First published2008
OrganizationInternational Cricket Council (ICC)
Base standardsBall tracking: Hawk-Eye or Virtual Eye

Sound analysis: Real Time Snicko

Infra-red imaging: Hot Spot
Batters and fielders wait for a decision to be shown on the big screen.

The Decision Review System (DRS), formerly known as the Umpire Decision Review System (UDRS), is a technology-based system used in cricket to assist the match officials in their decision-making. On-field umpires may choose to consult with the third umpire (known as an Umpire Review), and players may request that the third umpire consider a decision of the on-field umpires (known as a Player Review).

The main elements that have been used are television replays, technology that tracks the path of the ball and predicts what it would have done, microphones to detect small sounds made as the ball hits bat or pad, and infra-red imaging to detect temperature changes as the ball hits the bat or pad.

While on-field Test match umpires have been able to refer some decisions to a third umpire since November 1992, the formal DRS system to add Player Reviews was first used in a Test match in 2008, first used in a One Day International (ODI) in January 2011, and used in a Twenty20 International in October 2017.

History

DRS was preceded by a system to allow on-field umpires to refer some decisions to the third umpire to be decided using TV replays, in place since November 1992.

The system is based on the concept of Player - Referral conceived by Senaka Weeraratna in 1997.[citation needed] Player Reviews and additional technology were first introduced in Test cricket to review controversial decisions made by the on-field umpires as to whether or not a batter had been dismissed. The Player Referral system was first tested in an India v. Sri Lanka match in 2008,[1][2] and was officially launched by the International Cricket Council (ICC) on 24 November 2009, during the first Test between New Zealand and Pakistan at the University Oval in Dunedin.[3][4] It was first used in One Day Internationals (ODI) in January 2011 during England's tour of Australia.[5] The ICC initially made the UDRS mandatory in all international matches,[6] but later made its use optional, so that the system would only be used if both teams agree. The ICC has agreed to continue to work on the technology and will try to incorporate its use into all ICC events.[7]

In October 2012, the ICC made amendments on lbw protocols, increasing the margin of uncertainty when the ball hits the batsman's pad.[8] In July 2016, the rules were amended once again, reducing the margin of uncertainty.[9][10] The updated rules were first used in the ODI match between Ireland and South Africa in September 2016.[11]

In September 2013, the ICC announced that for a trial period starting in October 2013, a team's referrals would be reset to two after 80 overs in an innings in Test matches. Previously each team had a maximum of two unsuccessful reviews per innings.[12]

Starting in November 2014 from Australia's ODI series versus South Africa, the field umpires' communications have also been broadcast to the viewers. Whenever a decision is reviewed by the TV umpire, their communication with the field umpire can be heard.[13]

In February 2017, the ICC agreed the use for all future ICC World Twenty20 tournaments, with one review per team.[14] The first T20 tournament to use the technology was the 2018 ICC Women's World Twenty20.[15] It was used in the knockout stages of Pakistan Super League 2017, which was the first time DRS used in a T20 league. DRS was used for the first time in a Twenty20 International in the India–Australia T20I series in October 2017.[16]

Under the new ICC rules of November 2017, there would no longer be a top-up of reviews after 80 overs in Test matches, and teams will have only 2 unsuccessful reviews every innings. However, teams would no longer lose a review for an "umpire's call" (a ruling in which the on field's umpire's ruling stands due to inconclusive data) on an LBW review.

In 2020, the requirement to appoint neutral match officials was temporarily suspended due to the logistical challenges with international travel during the COVID-19 pandemic. Following from this change, the number of unsuccessful reviews per test innings was raised from 2 to 3 keeping in mind that there may be less experienced umpires on duty at times.[17]

From 1 June 2023, the "soft-signal" requirement for umpires when referring catches was scrapped as they were "unnecessary and at times confusing".[18][19]


Components

The components of DRS are:

A typical "snick" shown in the Snickometer display.
A typical edge shown in the Hot Spot display.
  • Video replays, including slow motion.
  • Hawk-Eye,[20] or Virtual Eye (also known as Eagle Eye): ball-tracking technology that plots the trajectory of a bowling delivery that has been interrupted by the batter, often by the pad, and can predict whether it would have hit the stumps.
  • Real Time Snicko (RTS) or Ultra-Edge[21][22][23] (Hawk-Eye Innovations): directional microphones to detect small sounds made as the ball hits the bat or pad. The use of the original Snickometer was superseded by Real Time Snicko in 2013.[24][25][26][27][28] RTS is calibrated each morning without needing manual syncing during play.[29] The third umpire interprets RTS/Ultra-Edge data by checking if an audio spike occurs on the frame before, on the frame, or the frame after the ball passes the bat.[30][31]
  • Hot Spot: Infra-red imaging system that shows where the ball has been in contact with bat or pad. Improved cameras were introduced for the 2012 season.[32] The system came under fire after the 2013 Ashes in England.[33] It was claimed that using silicone tape prevented faint edges being picked by Hot Spot, which was later confirmed by a MIT report.[34]
Comparison of ball-tracking technology
System No. of cameras Camera framerate
Hawk-Eye 6[35] 340 fps[35]
Virtual Eye (Eagle Eye) 4[36] 230 fps[36]

System

Umpire reviews

In many cases, the event occurs in a fraction of a second. At their discretion, on-field umpires may request the Third Umpire reviews the following dismissal decisions:[37]

  • Run out. If the on-field umpires are unable to decide if the batsman is out, they may request the third umpire to ascertain whether the batsman had made it home. Also the case where both batsmen have run to the same end and the on-field umpires are uncertain over which batsman made his ground first. An example of this was the Third Test between New Zealand and the West Indies in 2006.[38]
  • Caught and Obstructing the field if both umpires are unsure. In some cases the fielder may catch the ball a few inches above ground level. If the umpire's vision is obscured or is unsure if the ball bounced before the fielder caught the ball, he can refer the decision. The third umpire also checks whether the delivery was a no-ball and whether the batsman hit the ball.
  • Whether the delivery causing any dismissal was a no-ball.

Note the on-field umpires may not request the Third Umpire review an LBW decision (apart from whether the delivery was a no-ball).

The on-field umpires may also request the Third Umpire reviews the following:

  • Boundary calls (to see if a batter hit a four or a six). In some cases the ball may bounce just a foot inside the boundary rope resulting in four runs. If the umpire needs to ascertain if it had been a 4 or a 6, he may consult the third umpire. Near the boundary, often a fielder may dive to save the ball from travelling beyond the boundary. If the fielder makes any simultaneous contact with the boundary and the cricket ball, 4 runs are declared. A third umpire may also be consulted in such a case.
  • Whether the ball has hit cameras on or over the field of play.

Umpire Reviews are also available to the on-field umpires when there is a Third umpire but the full UDRS is not in use. In this case, the Third umpire uses television replays (only) to come to a decision, and not the additional technology such as ball-tracking.[39]

Player reviews

Scoreboard showing number of DRS unsuccessful Player Reviews remaining for India (2) and England (2).
Scoreboard showing number of DRS unsuccessful Player Reviews remaining for India (2) and England (2).

A fielding team may use the system to dispute a "not out" decision and a batting team may use it to dispute an "out" decision. The fielding team captain or the batter being dismissed invokes the challenge by signalling a "T" with the arms or arm and bat. A challenge is only used in situations that did or could result in a dismissal: for example, to determine if the ball is a legal catch (making contact with the batter's bat or glove and not touching the ground before being held by a fielder), or if a delivery made the criteria for an LBW dismissal.

Once the challenge is invoked, acknowledged, and agreed, the Third Umpire reviews the play.

Each team can initiate referrals until they reach the limit of unsuccessful reviews.[40] This limit is three unsuccessful review requests per innings during a Test match, and two unsuccessful review requests per innings during a One Day International or T20I (This limit was temporarily been raised to three per innings for tests and two for one-day matches from July 2020 as a COVID-19-related rule change but has since become permanent.[41]). From 2013 until September 2017, the number of reviews available for a team in a Test innings was topped-up to two after 80 overs. From October 2017, if the on-field decision remains unchanged because the DRS shows "umpire's call", the team will not lose its review.[42][43][44]

Umpire's call

As DRS become more commonplace in the game, there were perceptions that the game was becoming too forensic and technical in decision-making and that there was a risk on-field umpires would become nothing more than "glorified coat stands".[45]

To better finesse the system 'Umpire's Call' was introduced in 2016 by the International Cricket Council. Umpire's Call is a way of saying the original decision made by the on-field umpire should stand. The rules of the referral system say that there needs to be a "clear mistake" by the on-field umpire to reverse the decision.

There are numerous parameters by which a leg before wicket (LBW) decision is adjudged to be a clear mistake, including:

i) did the ball pitch in line with the stumps?
ii) did the batsman hit the ball first with his bat? (i.e. the ball hitting the pad first is a pre-condition of any decision to be given out to an LBW call)
iii) did the ball hit the batsman's pad in line with the stumps?
iv) what percentage of the ball hit the stumps? (usually decided by hawk-eye "ball tracking" system)

Umpire's Call is a way of saying that there is not a "clear mistake", and therefore the original on-field decision should stand. Furthermore, if the original decision stands as Umpire's Call, then the appealing team retains the review.[46]

The implementation of Umpire's Call has been noted in other sports whereby similar issues have arisen in the case of highly-marginal decisions (i.e. not a "clear mistake) which are perceived to be unfairly decided by forensic and technical means.[47][48][49]

On April 4, 2021, in the International Cricket Council committee meeting led by Anil Kumble, the height margin of the Wicket Zone was lifted to the top of the stumps to ensure the same Umpire's Call margin around the stumps for both height and width.[50]

Final decision

The third umpire then looks at various TV replays from different angles, comes to a conclusion, and then reports to the on-field umpire whether their analysis supports the original call, contradicts the call, or is inconclusive. The on-field umpire then makes the final decision: either re-signalling a call that is standing or revoking a call that is being reversed and then making the corrected signal. Only clearly incorrect decisions are reversed; if the Third Umpire's analysis is within established margins of error or is otherwise inconclusive, the on-field umpire's original call stands.[51]

Officiating replay system

In 2013, ICC tested a broadcaster-free replay system. Under the experiment, a non-match umpire sits in a separate room with a giant monitor and has discretion over which replays to see rather than relying on the broadcaster. The non-match umpire mirrors the role of the third umpire without having the duty of making adjudications. The system was first used in an Ashes Test (where Nigel Llong performed the duties of non-match umpire) and was repeated in a Pakistan-Sri Lanka ODI.[52]

After The Ashes in 2013, the ICC has started to take steps to give third umpire access to instant replays. This is regardless of calls being referred to by on-field umpires. By doing so, ICC wants to make sure that any obvious mistakes are avoided in future.[53]

Reception

The Decision Review System has generally received positive response from players and coaches since its launch. Because of its positive response, the ICC has attempted to apply uniform application of DRS in all cricket games around the world, but this has been difficult for some countries to implement. Some countries, especially the poorer ones, are unable to afford the technology and choose to use parts of it or not use it at all.[54] The technology is often used by broadcasters to bring an even more vivid analysis of specific plays and games. It was designed to eradicate the errors of umpires, and it has done so in many games.

However, there have been some negative responses to the DRS technology as well. West Indies legend Joel Garner labelled the system a "gimmick".[55] Another West Indian Ramnaresh Sarwan said that he was not a supporter of the experimental referral system.[56] Former umpire Dickie Bird also criticised the system, saying it undermines the authority of on-field umpires.[57] The BCCI has expressed a skeptical view on the adoption of the system if it is near perfect.[58] Pakistani spinner Saeed Ajmal expressed dissatisfaction over the Decision Review System after a semi-final of the 2011 Cricket World Cup against India. He said that DRS showed the line of the ball deviating more than it actually did.[59] Hawk-Eye officials admitted in December 2014 that their review technology made an error in a decision to give Pakistan opener Shan Masood out in the second Test against New Zealand in Dubai (17-21 November 2014). At a meeting held at the ICC office in Dubai two weeks later, Hawk-Eye is understood to have conceded to Pakistan captain Misbah-ul-Haq and team manager Moin Khan that the projection used by their technology for the Leg before wicket decision was incorrect.[60] Also, a challenge can only be made by the captain within a 15-second window from when an initial decision is made, but it can be lengthened if no clear decision is made, especially they are assumed not out if there is no reaction by the umpire.

During the 2012/2013 domestic season Cricket Australia trialed a review system in the domestic one day competition where the third umpire could intervene and review any out or not out decision. The review system was unpopular among players and critics, which the Australian International Twenty20 captain George Bailey calling the system "shocking and embarrassing".[61] The review system was dropped by Cricket Australia after only two rounds of the competition.[62]

During an ODI between Australia and South Africa in June 2016, Hawk-Eye's accuracy came under criticism after AB de Villiers was dismissed clean bowled by Josh Hazlewood but subsequent Hawk-Eye trajectory prediction of the same delivery showed that the ball would go over the stumps.[63]

Player Review statistics

An analysis of more than 2,100 Player Reviews between September 2009 and March 2017 found that:[64][65]

  • 26% of Player Reviews resulted in on-field decisions being overturned.
  • Reviews by batsmen were less frequent than reviews by bowling teams, as 41% of reviews were by batsmen and 59% by bowling teams.
  • Reviews by batsmen were more likely to be successful, with a 34% success rate, compared to a success rate of about 20% for bowling teams.
  • 74% of referrals were for LBW, 18% for wicketkeeper catches, and the rest for catches elsewhere or indeterminate reason. The success rate was only 22% for LBW, compared to 40% for wicketkeeper catches.
  • There were on average about 1.4 batting overturns and 1.2 bowling overturns per match. Initial fears that DRS would bring an increase in the number of dismissals have, therefore, not come true.
  • The UDRS claims to have 90% accuracy [66]

References

  1. ^ NDTVSports.com. "Umpiring decision review system on the cards – NDTV Sports". Archived from the original on 25 August 2016. Retrieved 29 November 2016.
  2. ^ "Umpire review system to be trialled in Sri Lanka-India Tests". ESPN Cricinfo. 16 June 2008.
  3. ^ "Decision Review System set for debut". Cricketnext.in. 23 November 2009. Archived from the original on 26 November 2009. Retrieved 18 February 2010.
  4. ^ "Official debut for enhanced review system". ESPNcricinfo. 23 November 2009. Archived from the original on 10 January 2010. Retrieved 18 February 2010.
  5. ^ "Referrals to be used in Australia-England ODI series". BBC Sport. BBC. 16 January 2011. Archived from the original on 8 August 2017. Retrieved 16 January 2011.
  6. ^ "Mandatory for all matches". Archived from the original on 1 July 2011. Retrieved 29 June 2011.
  7. ^ "No mandatory use of Decision Review System, says ICC". The Times of India. Archived from the original on 14 July 2014. Retrieved 16 May 2014.
  8. ^ "ICC paves way for Day-Night Tests". Wisden India. 29 October 2012. Archived from the original on 30 June 2015. Retrieved 30 October 2012.
  9. ^ "ICC approves changes to DRS playing conditions". ESPNcricinfo. Archived from the original on 3 July 2016. Retrieved 2 July 2016.
  10. ^ "ICC Annual Conference concludes in Edinburgh". ICC Development (International) Limited. 2 July 2016. Archived from the original on 8 October 2016. Retrieved 14 July 2016.
  11. ^ "South Africa-Ireland ODI first to feature new DRS". ESPNcricinfo. 26 September 2016. Archived from the original on 25 September 2016. Retrieved 26 September 2016.
  12. ^ "Reviews to be topped-up after 80 overs". Wisden India. 18 September 2013. Archived from the original on 9 July 2017. Retrieved 19 September 2013.
  13. ^ "Umpire communications to be broadcast". cricket.com.au. Archived from the original on 13 November 2020. Retrieved 13 November 2020.
  14. ^ "Big-Three rollback begins, BCCI opposes". ESPNcricinfo. 4 February 2017. Archived from the original on 5 February 2017. Retrieved 4 February 2017.
  15. ^ "Uniform DRS likely from October". ESPNcricinfo. 6 February 2017. Archived from the original on 6 February 2017. Retrieved 6 February 2017.
  16. ^ "Australia denied advantage of new rules". ESPNcricinfo. Archived from the original on 20 October 2020. Retrieved 13 November 2020.
  17. ^ "Interim regulation changes approved". icc-cricket.com. Archived from the original on 7 March 2021. Retrieved 27 January 2021.
  18. ^ "'Waste of time': ICC finally scraps soft signal rule after years of controversy". Fox Sports. 15 May 2023. Retrieved 28 December 2023.
  19. ^ "ICC scraps soft-signal rule for contentious catches". ESPNcricinfo. Retrieved 28 December 2023.
  20. ^ "Technology in Sports:DRS,GoalRef & HawkEye | TechBuzzIn™". TechBuzzIn™. 9 April 2017. Archived from the original on 26 April 2017. Retrieved 15 April 2017.
  21. ^ "Ultra-edge ready for Test use". ESPNcricinfo. Archived from the original on 14 November 2020. Retrieved 13 November 2020.
  22. ^ "Q&A with Geoff Allardice on the Loughborough technology trial". Archived from the original on 20 December 2016. Retrieved 10 December 2016.
  23. ^ "Why universal use of DRS is getting closer, but still not close enough | Mike Selvey". The Guardian. 20 October 2015. Archived from the original on 14 November 2020. Retrieved 13 November 2020.
  24. ^ "Hot Spot may earn Ashes reprieve". Archived from the original on 29 November 2016. Retrieved 29 November 2016.
  25. ^ TNN (7 July 2011). "'Hot spot's success rate is 90-95%'". The Times of India. Archived from the original on 6 September 2012. Retrieved 21 July 2013.
  26. ^ "Hawk-Eye needs a leap of faith - Srinivasan". Archived from the original on 2 February 2012.
  27. ^ "DRS: BCCI warms up to MIT-approved technology | Cricket News - Times of India". The Times of India. 20 October 2016. Archived from the original on 24 November 2020. Retrieved 13 November 2020.
  28. ^ "No HotSpot for India-England Tests". ESPNcricinfo.
  29. ^ "Snicko is Hot Spot's insurance policy". ESPNcricinfo. Archived from the original on 31 December 2020. Retrieved 7 January 2022.
  30. ^ "England baffled by Root's DRS dismissal". ESPN.com. 14 December 2013. Archived from the original on 11 November 2020. Retrieved 7 January 2022.
  31. ^ "Cricket: Talking points from day two of the Fifth Ashes Test". NZ Herald. Archived from the original on 7 January 2022. Retrieved 7 January 2022.
  32. ^ "New cameras should capture faintest of edges - Hot Spot inventor". Archived from the original on 11 January 2012.
  33. ^ "Hot Spot should be removed - Vaughan". BBC Sport. Archived from the original on 29 November 2020. Retrieved 13 November 2020.
  34. ^ Hoult, Nick (6 June 2016). "Hot Spot can be fooled by bat tape, say scientists". The Daily Telegraph. Archived from the original on 7 January 2022. Retrieved 3 December 2018.
  35. ^ a b "Cricket: Review scandal questions accuracy of Hawk-Eye technology". NZ Herald. Archived from the original on 30 November 2020. Retrieved 7 January 2022.
  36. ^ a b "Take DRS out of players' hands: Virtual Eye Head Ian Taylor". The New Indian Express. Archived from the original on 27 January 2021. Retrieved 7 January 2022.
  37. ^ "ICC Men's Test Match Playing Conditions Effective 1 September 2019". ICC. pp. Appendix D: Decision Review System (DRS), Section 2 Umpire Review. Archived from the original on 6 December 2019. Retrieved 1 January 2020.
  38. ^ "Bizarre Runout". YouTube.[dead link]
  39. ^ "ICC Men's One Day International Playing Conditions Effective 30 September 2018". ICC. 30 September 2018. Archived from the original on 6 December 2019. Retrieved 14 January 2020. Appendix D, paragraph 1.1.6, THIRD UMPIRE (NON-DRS), Replays that can be used: The third umpire shall only have access to replays of any camera images. Other technology which may be in use by the broadcaster for broadcast purposes (for example, ball-tracking technology, sound-based edge detection technology, and heat-based edge detection technology) shall not be used during Umpire Reviews.
  40. ^ "Decision Review System (DRS)". Archived from the original on 18 December 2014. Retrieved 18 December 2014.
  41. ^ "How many reviews in Test cricket: Have number of DRS reviews changed in the COVID-19 era?". Archived from the original on 19 September 2020. Retrieved 14 August 2020.
  42. ^ "The new cricket rule changes coming into effect from September 28". ESPNcricinfo. Archived from the original on 7 April 2018. Retrieved 13 October 2017.
  43. ^ "Cricket to change, new rules on run-outs, bat size, poor behaviour from Sept. 28". Hindustan Times. 26 September 2017. Archived from the original on 13 November 2020. Retrieved 13 November 2020.
  44. ^ "Reviews to be reset after 80 overs". Archived from the original on 21 October 2017. Retrieved 21 October 2017.
  45. ^ "The problem with upholding the umpire's call". ESPNcricinfo. 25 June 2016. Archived from the original on 7 January 2022. Retrieved 30 August 2020.
  46. ^ "ICC's Cricket Committee backs the controversial "umpire's call" rule in DRS". CricketTimes.com. Archived from the original on 24 March 2021. Retrieved 24 March 2021.
  47. ^ "Football is getting VAR wrong – it should learn from cricket". New Statesman. 21 June 2019. Archived from the original on 8 August 2020. Retrieved 30 August 2020.
  48. ^ "DRS vs VAR: Four ways football can learn from cricket's technology". cricket365. 21 November 2019. Archived from the original on 20 October 2020. Retrieved 30 August 2020.
  49. ^ "Solving the Premier League's VAR mess: Our reporters' proposals on how to end technology debate". The Telegraph. 30 December 2019. Archived from the original on 22 July 2020. Retrieved 30 August 2020. Football should take the lead from cricket when it comes to the use of video technology, especially with the closest calls. The first decision of the on-field umpire still counts with LBW appeals that clip the stumps, or contentious catches which may or may not have bounced into the hand. The same logic should apply to football's offside rule.
  50. ^ "Anil Kumble-led ICC Committee makes key changes in LBW reviews, but sticks with "Umpire's Call"". CricketTimes.com. Archived from the original on 4 April 2021. Retrieved 4 April 2021.
  51. ^ "The Ashes 2010: How the Umpire Decision Review System works". Archived from the original on 18 December 2014. Retrieved 18 December 2014.
  52. ^ "Officiating Replay System trial for Pakistan-SL series". Archived from the original on 19 August 2017. Retrieved 29 November 2016.
  53. ^ "ICC trials instant replays for third umpires". ESPNcricinfo. Archived from the original on 30 December 2018. Retrieved 17 January 2020.
  54. ^ "Decision Review System: Explaining the technology behind it". sportskeeda. Archived from the original on 17 April 2021. Retrieved 31 March 2020.
  55. ^ "Garner labels review system as a 'gimmick'". The Independent. London. 10 December 2009. Archived from the original on 15 December 2018. Retrieved 18 February 2010.
  56. ^ Weaver, Paul (6 December 2009). "Sarwan unhappy with umpire review system despite reprieve". The Guardian. Archived from the original on 4 November 2013. Retrieved 18 February 2010.
  57. ^ "Dickie Bird criticises review system". ESPNcricinfo. 7 December 2009. Archived from the original on 7 January 2022. Retrieved 18 February 2010.
  58. ^ "BCCI open to use DRS if its near perfection: Anurag Thakur". 3 October 2016. Archived from the original on 10 November 2016. Retrieved 29 November 2016.
  59. ^ "Ajmal speaks against DRS". The News International. 2 April 2011. Archived from the original on 5 April 2011. Retrieved 3 April 2011.
  60. ^ "Hawk-Eye admits technical error in Masood dismissal". ESPN Sports Media Ltd. 10 December 2014. Archived from the original on 21 December 2014. Retrieved 8 January 2015.
  61. ^ "'Shocking and embarrassing' system may be short-lived | ESPNcricinfo.com". ESPNcricinfo. Archived from the original on 14 July 2020. Retrieved 14 July 2020.
  62. ^ Hogan, Jesse (28 November 2012). "One-dayer umpire shift". The Sydney Morning Herald. Archived from the original on 14 July 2020. Retrieved 14 July 2020.
  63. ^ Otto, Tyson (15 June 2016). "New review scandal shocks cricket". news.com.au. Retrieved 13 January 2022.
  64. ^ Charles Davis. "Statistics and the DRS" (PDF). Archived (PDF) from the original on 13 October 2017. Retrieved 12 October 2017.
  65. ^ "The art of the review". ESPN. 1 June 2017. Archived from the original on 13 October 2017. Retrieved 12 October 2017.
  66. ^ Slnha, Pandey, & Singh (May 2017). "A research on reliability of Umpire Decision Review System in cricket" (PDF). International Journal of Scientific & Engineering Research. 8: 60–62. Archived (PDF) from the original on 27 February 2020. Retrieved 27 February 2020.{{cite journal}}: CS1 maint: multiple names: authors list (link)
Retrieved from "https://en.wikipedia.org/w/index.php?title=Decision_Review_System&oldid=1192263391"