Mannone was understudy to Łukasz Fabiański during Arsenal's 2007–08 League Cup campaign. However, he was an unused substitute in all of the club's five matches in the competition, before they were knocked-out in the semi-finals by North London rivals Tottenham Hotspur. On 19 December 2007, Arsenal announced that Mannone had signed a new long-term contract. On 19 April 2008, he was named on the bench for a Premier League game for the first time, in Arsenal's 2–0 win against Reading at the Emirates Stadium. But he was an unused substitute as Jens Lehmann played the entire match.