Ryall playing for the Olyroos in 2011
|Full name||Sebastian John Henry Ryall|
|Date of birth||18 July 1989|
|Place of birth||Sydney, New South Wales, Australia|
|Height||1.80 m (5 ft 11 in)|
|Playing position||Centre Back / Right Back|
|* Senior club appearances and goals counted for the domestic league only and correct as of 21 May 2017|
Ryall played junior football for West Pymble Football Club in Sydney. Ryall later played for the AIS in the Victorian Premier League before signing for Melbourne Victory on a 2-year contract in August 2007.
He made his first appearance for the club in their round 3 match against Adelaide United and played in their Grand Final win over Adelaide in March 2009. In April 2009 he signed with Sydney FC for the 2009/2010 A-League campaign.
He re-signed with Sydney FC for a further 2 seasons, on 24 August 2010.
Ryall scored his first goal for Sydney FC in the 2011-12 A-League season with a dramatic equaliser in the 90th minute, against his former team Melbourne Victory on 26 January. Ryall's strike came less than a minute after being brought on as a substitute . Ryall continued to score important goals for Sydney against his former club, including 3 goals in 4 appearances against the Victory during the 2013-14 A-League season with goals in the Round 5, 3-2 win at Allianz Stadium, Round 16, 5-0 win on Australia Day at Etihad Stadium in Melbourne, and again in the 1-2 2013-14 Elimination Final loss against the Victory at Etihad.
Controversy surrounded Ryall during the 2014-15 A-League round 17 clash vs the Melbourne Victory when he was awarded a penalty following a possession contest with Victory player Gui Finkler. Initial replays appeared to show Ryall simulating contact with Finkler's leg. At the time, Melbourne Victory were leading 2-1, and the resulting conversion of the penalty kick allowed Sydney FC to get back into the game. The decision to award the penalty was heavily criticized by media commentators, managers, players, and pundits alike, with former player and Fox Sports commentator Mark Bosnich reacting angrily to the decision. Melbourne Victory player Kosta Barbarouses claimed he had "lost respect" for Ryall over the incident. Ryall also drew criticism from Sydney FC coach Graham Arnold, and CEO of the club Tony Pignata over his reaction following the awarding of the penalty where he appeared to clip Finkler over his head. On 19 February, Ryall was cleared of diving by the FFA Match Review Panel, with the board taking 2 hours to clear him following reviewing slowed down footage, which showed Ryall's leg being clipped by Finkler.
During round 12 in a match against the Central Coast Mariners of the 2015/16 season, Ryall was handed the captain's armband after regular skipper Alex Brosque limped off with a recurring hamstring injury and both vice-captains Jacques Faty and Shane Smeltz starting on the bench. Ryall proceeded to earn multiple best on ground awards during his stint as skipper.
On the 17th of January 2018, Ryall had his contract terminated with Sydney FC at his request in order to seek a break from football, stating that he had grown "disillusioned" and grown out of favour with the sport. In doing so, allows for Ryall to pursue other opportunities outside of football and a hope to rekindle his passion for the game.
Throughout 2007 and 2008 Ryall was the captain of the Australian U-20 side. Due to a suspension, Sebastian missed out on selection for the 2009 FIFA U-20 World Cup due to his criminal charges, where which he would have been assured a spot in the team. After a lengthy absence from Australia's national teams, in September 2010 he was called up to the Australian under-23 side by coach Aurelio Vidmar for a Four Nations Tournament held in Vietnam.
Ryall was charged, on 15 May 2009, with engaging in a sexual act with a 13-year-old girl. The alleged incident happened in January 2008, while he was playing with Melbourne Victory. He was suspended from participation in football matches in Australia, until 3 September as well as being stood down from the national youth team by Football Federation Australia Chief Executive Officer Ben Buckley for bringing the game into disrepute. On Monday 25 January 2010, he was committed to stand trial on the case after his committal hearing at Sydney's Downing Centre Local Court  On 15 May 2010, the Director of Public Prosecutions dropped the charges against Ryall  After a submission by Ryall's legal team that at the time of the alleged incident, he believed the girl to be over the legal age of 16  and that they were "just kissing" 
- As of 19 December 2018
|Australian Institute of Sport||2007||Victorian Premier League||24||0||—||—||—||24||0|
- A-League Championship: 2008–09
- A-League Premiership: 2008–09
- A-League Pre-Season Challenge Cup: 2008
- "Victory sign young Socceroos captain". Sportal.com.au. 28 August 2007. Retrieved 10 October 2007.
- "Sebastian Ryall moves to Sydney FC". The Australian. 7 April 2009. Retrieved 13 May 2009.
- "Young gun Ryall re-signs with Sky Blues". Sydney FC. 24 August 2010. Archived from the original on 25 February 2011. Retrieved 24 August 2010.
- Lucius, Adam (9 November 2014). "Sydney win dramatic Big Blue clash". Football Federation Australia (via omnisport). Archived from the original on 13 November 2014. Retrieved 25 February 2015.
- Lynch, Michael (26 January 2014). "Sydney FC thrash hapless Melbourne Victory 5-0". Sydney Morning Herald. Retrieved 25 February 2015.
- Davutovic, David (18 April 2014). "Gui Finkler's late winner sees Melbourne Victory knock Sydney FC out of the A-League finals". Herald Sun. Retrieved 25 February 2015.
- "Sydney FC plays out 3-3 A-League draw with Melbourne Victory". ABC. 14 February 2015. Retrieved 25 February 2015.
- "Big Blue: Mark Bosnich slams Strebre Delovski's penalty decision in Allianz Stadium 3-3 thriller". Daily Telegraph. 14 February 2015. Retrieved 25 February 2015.
- Lerner, Ronnie (17 February 2015). "Melbourne Victory's Kosta Barbarouses has lost respect for Sydney FC's Sebastian Ryall following controversial penalty". Sydney Morning Herald. Retrieved 25 February 2015.
- "Sebastian Ryall must control himself better, says Sydney FC coach Graham Arnold after diving furore". ABC. 19 February 2015. Retrieved 25 February 2015.
- Barbieri, Paul. "Pignata blasts Ryall for Finkler flick". Sportal. Retrieved 25 February 2015.
- Bossi, Dominic (19 February 2015). "Sydney FC defender Sebastian Ryall cleared of diving against Melbourne Victory". Sydney Morning Herald. Retrieved 25 February 2015.
- Smithies, Tom (24 February 2014). "Sydney FC re-sign Seb Ryall and Rhyan Grant, switch focus to securing Shane Smeltz's future". Daily Telegraph. Retrieved 25 February 2015.
- "A-League star Sebastian Ryall 'had sex with 13-year-old'". Adelaide Now. 15 May 2009. Archived from the original on 17 May 2009. Retrieved 15 May 2009.
- "Young Socceroo stood down over sex act with girl charge". smh.com.au. 15 May 2009. Retrieved 15 May 2009.
- "Sydney FC recruit Sebastian Ryall stood down while he fights sex charge". The Australian. 15 May 2009. Archived from the original on 18 May 2009. Retrieved 15 May 2009.
- "BREAKING NEWS: Sydney FC Player Sebastian Ryall In Child Sex Scandal". goal.com. 15 May 2009. Retrieved 15 May 2009.
- "A-League player faces child sex charges". abc.net.au. 15 May 2009. Retrieved 15 May 2009.
- "Player suspended following under-age sex charge". USA Today. 15 May 2009. Retrieved 15 May 2009.
- "Young Socceroo accused of sex with girl, 13". Sydney Morning Herald. 25 January 2010. Retrieved 25 January 2009.
- "Sex charges dropped against Ryall". ABC. 16 May 2010. Retrieved 18 May 2010.
- Kennedy, Les (16 May 2010). "Soccer star in the clear on under-age sex charge". The Sydney Morning Herald. Retrieved 18 May 2010.
- "Player alleges 'the girl said she was 16'". AAP. 22 October 2009.
- "Sebastian Ryall Appearance Details". www.aleaguestats.com. Retrieved 19 December 2018.