Throughout the 2008–09 season, O'Shea became a regular within the team, deputising at right-back because of injuries to Gary Neville and Wes Brown. On 20 January 2009, O'Shea scored his first goal of the season against Derby County in the second leg of the League Cup semi-final. O'Shea then started the 2009 Football League Cup Final, before being replaced by Nemanja Vidić on 76 minutes, United won the game 4–1 on penalties. On 29 April 2009, O'Shea scored the only goal of the game in the first leg of the Champions League semi-final against Arsenal, this set United up to go on and win in the second leg by 4–1 on aggregate. O'Shea started and played the full 90 minutes in the 2009 Champions League Final 2–0 loss to Barcelona, and by many accounts was one of United's better performers on the night. Sir Alex Ferguson had promised O'Shea, who was an unused substitute in the 2008 Champions League Final, a starting place in the 2009 final for his contribution to the team that season.