player with big potential". The transfer was free, although Southend would receive a percentage of any transfer fee for O'Keefe in his first 36 months at Selhurst Park. He made his debut for the club on 20 November 2010 as a substitute in place of Paddy McCarthy during a 3–2 defeat to Sheffield United, later being substituted himself in the 89th minute of the match for Pablo Couñago as Palace pushed for an equaliser. In his first season at Selhurst Park, O'Keefe was a backup player in the squad and made just four appearances during the course of the season. In the 2011–12 season, O'Keefe was given a chance to impress early on in the season in the League Cup, playing five times in the competition during the season as the team reached the semi-final, including starting in the team's 2–1 quarter final victory over Manchester United on 30 November 2011 at Old Trafford. Later in the season, O'Keefe was part of the end of season run in due to injuries and finished the season with 19 appearances for the first team, which saw him offered a new three-year contract with Palace that would last until summer 2015. During the 2012–13 season, Palace achieved promotion to the Premier League via the Championship play-offs after finishing fifth. O'Keefe featured just five times in the league during the season although he did make two appearances during the play-offs, replacing Wilfried Zaha as a late substitute during the second leg of their semi-final victory over Brighton & Hove Albion, and then playing the majority of the 2013 Championship play-off Final after replacing Kagisho Dikgacoi due to injury after just 17 minutes as Palace claimed a 1–0 victory in extra-time to earn promotion. At the start of the club's Premier League campaign the following season, on 31 August 2013, O'Keefe sealed a 3–1 victory in Palace's first three points of their Premier League return in the 92nd minute at home to Sunderland with a curling 20-yard shot after coming on as a late substitute, the first senior goal of his career and what later turned out to be his only goal for Palace. At the start of the 2014–15 season, O'Keefe featured in Palace's opening two matches of the Premier League season, defeats to Arsenal and West Ham United, but suffered an ankle injury in the latter which kept him out of the team