[2] Clarke started playing football with local club Newtown Schoolboys in his home town of Newtownmountkennedy (County Wicklow).
[5] However, he returned to the side in 2001–02 and helped Stoke gain promotion by beating Brentford in the 2002 Football League Second Division play-off final.
[citation needed] Clarke signed for West Ham for a fee of £275,000 at the end of July 2005, brought to the club by the then manager, Alan Pardew, who wanted another left-sided player.
[11] During the League Cup tie between Nottingham Forest and Leicester on 28 August 2007, Clarke collapsed and suffered a cardiac arrest in the changing rooms at the City Ground causing the match to be abandoned at half-time, with the score at 1–0.
[12] In an act of sportsmanship, Leicester allowed Forest to score the opening goal on the re-match to regain the advantage they had when the first game was abandoned.
[15] "I remember feeling a bit lethargic on the field in the first half, and I was involved in a collision with our goalkeeper Paul Henderson, which led to their goal.
When you think about Sevilla player Antonio Puerta (who collapsed last Saturday and died on Tuesday), it goes without saying that a day won't pass when I don't cherish every moment in my life".Clarke told Sky Sports on 12 September 2007 that he was still hopeful of playing again,[16] but he never made another appearance for Leicester following the incident, and he returned to Sunderland in November 2007.