Signed by Arsène Wenger in the summer of 2003 from AS Cannes for £250,000, Clichy plays the position of left back for Arsenal, although he had to be content with playing understudy to England international Ashley Cole during his first three seasons at the club.
His 12 appearances in the Premiership in Arsenal's victorious 2003-04 season were enough to earn him a winners medal. In doing so, he set the record for youngest winner of a Premiership champions medal.
After Ashley Cole suffered a fractured foot in October 2005, it seemed that Clichy would earn some valuable first-team action during Cole's time out; indeed, with rumours linking Cole with a transfer to Spain, it seemed that Clichy could make a strong case for continual first-team action. However Clichy ironically suffered an injury identical to Cole's, leaving Arsenal with a crisis at the left-back position.
Clichy returned to first team action on April 25, 2006 in a Champions League semi-final against Villarreal, and came on as a substitute for the injured Mathieu Flamini. Clichy suffered a re-occurrence of his injury and missed the end of the season including the Champions League Final, and would not return to the first team until 14 October 2006.
When Cole left for Chelsea in August 2006, Clichy became the first choice left-back at Arsenal. As Cole's understudy, Clichy made 62 appearances (including 39 in the league) for Arsenal in three seasons. In the season which followed Cole's departure, Clichy made 27 league appearances in a total of 40, and has since become Arsenal's first-choice left back. In the 2007-08 season, Clichy was selected in the PFA Team of the Year as left back. This fine form was rewarded on 20 June 2008, when he signed a new "long-term" contract. He came in second in the Arsenal fans' poll for Player of the Season.