Kirkland made his debut for Liverpool in October 2001, but mostly served as understudy to first-choice goalkeeper Jerzy Dudek during the 2001–02 season. During the following season, costly errors by Dudek in a league fixture against Manchester United resulted in manager Gérard Houllier handing the first team place to Kirkland in December. He played 14 consecutive matches, during which he kept six clean sheets, but sustained an ankle injury in January 2003, which ruled him out for the rest of the 2002–03 season, meaning he missed the victorious 2003 League Cup Final. He spent six weeks out of action after tearing his groin whilst on England under-21 duty in September 2003. He fractured a finger in December 2003, and was ruled out of action for four months after undergoing surgery to repair it.