|Irish name||Gearóid Ó hAinfidh|
4 April 1977|
Athlone, County Westmeath, Ireland
|Height||6 ft 4 in (1.93 m)|
|Occupation||Business Development Director|
Hanniffy made his first appearance for the team during the 1997 National League and subsequently became a regular member of the starting fifteen until his retirement prior to the 2008 championship. During that time he won one All-Ireland medal and one National Hurling League (Division 2) medal. Hanniffy was an All-Ireland runner-up on one occasion.
Hanniffy plays his club hurling with Birr and has enjoyed much success during a lengthy career.
By 1997 Hanniffy was a regular member of the starting fifteen. That year he won his first county championship medal following a 0–14 to 2–4 defeat of Seir Kieran. He later added a Leinster medal to his collection following an 0–11 to 0–5 defeat of Castletown. The subsequent All-Ireland final saw Birr take on Sarsfield's of Galway. Darren Hanniffy scored the only goal of the game after just five minutes and gave Birr a lead that they would never surrender. A 1–13 to 0–9 victory gave Hanniffy his first All-Ireland medal.
After surrendering their titles the following year, Birr bounced back in 1999. A 3–15 to 1–11 defeat of St. Rynagh's gave Hanniffy a second championship medal. A subsequent 1–16 to 0–11 defeat of Castletown gave Hanniffy a second Leinster medal.
Hanniffy won further championship medals in 2000 and 2001 as Birr retained their status as the kingpins of Offaly hurling. Once again Birr defeated Castletown in the provincial decider to give Hanniffy his third Leinster medal. Once again Birr qualified for the All-Ireland final with Clarinbridge providing the opposition. A Declan Pilkington goal inside sixty seconds was the perfect start, although the Westerners did recover to lead by 1–4 to 1 -2 at the break. With wind advantage, Birr took control and secured a 2–10 to 1–5 victory. It was Hanniffy's second All-Ireland medal.
Birr continued their dominance in 2002 with Hanniffy winning a fifth championship medal following a 3–12 to 2–7 defeat of Kilcormac-Killoughey. He later added a fourth Leinster medal to his collection following a 2–5 to 1–2 defeat of Young Irelands in deplorable conditions. Birr later faced Dunloy in the All-Ireland decider. At the third time of asking Birr finally retained the title with a 1–19 to 0–11 victory. It was Hanniffy's third All-Ireland medal.
It was the start of another great run of success for Birr as the club retained their titles in 2006 and 2007. Later that year Hanniffy won his fifth and final Leinster medal as Birr narrowly defeated Ballyboden St. Enda's by 1–11 to 0–13. Birr later had the chance to make history by becoming the first club side to win five All-Ireland titles, however, Portumna easily defeated Hanniffy's side by 3–19 to 3–9 in the decider.
By 1998 Hanniffy was a regular impact sub for Offaly's championship campaign. He lined out in his first provincial decider that year, however, Kilkenny defeated Offaly by 3–10 to 1–11. This defeat prompted the Offaly manager, Babs Keating, to describe the team as "sheep in a heap", and he promptly resigned. It looked as if Offaly's championship hopes were in disarray, however, they overcame Antrim in the All-Ireland quarter-final and qualified to meet Clare in the semi-final. The first game ended in a draw and had to be replayed, however, the replay was ended early because of a time-keeping error by the referee Jimmy Cooney. Following a protest on the pitch of Croke Park by the Offaly supporters it was decided that Clare and Offaly would meet for a third time. Hanniffy's side won the third game and qualified to play Kilkenny in the final. On that day Brian Whelahan delivered one of his greatest-ever Offaly performances, scoring 1–6. Offaly reversed the Leinster final defeat by winning the All-Ireland final by 2–16 to 1–13. It was Hanniffy's first All-Ireland medal.
Offaly surrendered their All-Ireland crown the following year but returned to the All-Ireland decider again in 2000 in a repeat of the Leinster final. Kilkenny's D.J. Carey capitalised on an Offaly mistake after just six minutes to start a goal-fest for "the Cats". Carey scored 2–4 in all, sharing his second goal with Henry Shefflin who also scored a goal in the second-half. At the full-time whistle Kilkenny were the champions by 5–15 to 1–14.
The following few seasons proved difficult as Kilkenny went on to dominated the provincial championship.
Following Offaly's relegation from Division 1 of the National League in 2008, Hanniffy decided to call time on his inter-county career.
As a player
- All-Ireland Senior Club Hurling Championship (4): 1995, 1998, 2002, 2003
- Leinster Senior Club Hurling Championship (6): 1994, 1997, 1999, 2001, 2002, 2007
- Offaly Senior Club Hurling Championship (11): 1994, 1997, 1999, 2000, 2001, 2002, 2003, 2005, 2006, 2007, 2008
- "Offaly brothers in arms". Irish Independent. 26 July 2003. Retrieved 2 December 2012.
- Hogan, Vincent (4 October 1999). "Whelahan experiment pays off for classy Birr". Irish Independent. Retrieved 2 December 2012.
- "Whelahan magic keeps Birr bandwagon rolling". Irish Independent. 29 November 1999. Retrieved 2 December 2012.
- "Birr pushed to the limit by battling St Rynagh's". Irish Independent. 8 October 2001. Retrieved 2 December 2012.
- Hogan, Vincent (17 December 2001). "Simple for Birr as Simon returns with interest". Irish Independent. Retrieved 2 December 2012.
- Hogan, Vincent (18 March 2002). "Birr's Semple sensation". Irish Independent. Retrieved 2 December 2012.
- "Whelahan and Claffey have it their own way". Irish Independent. 30 September 2002. Retrieved 2 December 2012.
- Hogan, Vincent (2 December 2002). "'Disgusted' Pat Joe lashes Offaly over snub". Irish Independent. Retrieved 2 December 2012.
- "Classy Birr too good for Dunloy". Breaking News website. 17 March 2003. Retrieved 2 December 2012.
- "Whelahan's amazing run continues". Irish Independent. 6 October 2003. Retrieved 2 December 2012.
- "Birr exact revenge in ruthless final display". Irish Independent. 17 October 2005. Retrieved 2 December 2012.
- "Hanniffy the Birr hero again". Irish Independent. 9 October 2006. Retrieved 2 December 2012.
- "Whelahan turns back the clock with vintage display as Birr power to their eleventh senior hurling championship title in 17 years". Irish Independent. 22 October 2007. Retrieved 2 December 2012.
- "Birr in seventh heaven after Leinster final win". Breaking News website. 2 December 2007. Retrieved 2 December 2012.
- "Canning masterclass seals Portumna glory". Irish Independent. 18 March 2008. Retrieved 2 December 2012.
- "Hanniffy inspired for Birr in tense decider". Irish Independent. 13 October 2008. Retrieved 2 December 2012.
- "Scannal: Long Hot Summer". RTÉ Television. 17 March 2008. Retrieved 1 December 2012.
- Moran, Seán (14 September 1998). "Offaly tune in, step up and prove an unstoppable force". Irish Times. Retrieved 4 November 2010.
- "Offaly hit Carlow for six". Irish Independent. 18 May 2005. Archived from the original on 18 February 2013. Retrieved 2 December 2012.
- "Hanniffy bows out". Hogan Stand website. 3 April 2008. Retrieved 2 December 2012.
| All-Ireland Club Hurling Final
|| Offaly Senior Hurling Captain