What might have been
Struck by illness on verge of Arsenal breakthrough and knee problems eventually drove him down the leagues and into retirement.
Narrowly missed out on World Cup squad in 2002 and career graph was heading in upward direction until hip problem shattered the Dubliner's dream.
Teenage prodigy who was highly rated by Alex Ferguson after joining Manchester United along with John O'Shea. Plagued by injuries and forced to retire in his 20s.
John Paul Kelly
Outstanding youth who chose Liverpool over others and then failed to settle. Returned to League of Ireland but lacked attitude to stay there and now playing at a low level of Leinster Senior League.
Gifted footballer who didn't make the best of his opportunity at Sunderland and is now without a club after parting company with Leyton Orient.
Regular at Championship level with Preston as a teenager, yet he failed to push on and ended up back in Ireland, eventually sacked by St Patrick's Athletic, who questioned his fitness.
Three in limbo
Always had his fair share of admirers, but has proven to be something of a nearly man at senior level, flirting with breakthrough at Manchester City before ending up in Scotland and now Middlesbrough. Injury-prone.
A member of an all-conquering Home Farm schoolboy side, and a strong defensive leader earmarked for stardom at Celtic. Loan spell at Reading last year was disaster, but performed better at Ipswich until injury struck.
Another Home Farm boy who broke through to the Championship with Ipswich at age of 17, but failed to really push on, with arrival of Roy Keane as manager eventually resulting in a parting of ways. Now trying to rebuild his reputation with Crystal Palace.
Three back home
Much fanfare when he headed for Arsenal as a silky ball-playing midfielder, with the 'next Liam Brady' tag attached. Now at Shamrock Rovers, where he is sometimes considered a luxury.
Suffered a few setbacks just as he forced his way into Mick McCarthy's plans at Sunderland in 2003. Excellent for Sligo this term, and could yet move back across the water. Keith Fahey proves it's never too late.
Made Sunderland debut against Arsenal eight years ago, yet was forced to retire from game due to crippling knee problems which struck 12 months later. Worked on his fitness to come back and rebuild career with Bohs.