Born in Bermondsey, London, Rooney joined Gillingham as an apprentice professional in 2007. He forced his way into the first team squad in early December 2008 and was an unused substitute in the FA Cup second round replay at Stockport County. In early 2009 he was loaned out to Lewes of the Conference National, where he made six appearances. He turned full-time professional with Gillingham at the start of the 2009–10 season and made his first team debut against Plymouth Argyle in the first round of the Football League Cup. His first Football League appearance was in the 3–0 home win over Exeter City on 5 September 2009, in which he scored his first ever goal for the Gillingham senior team. On 15 March 2010, Rooney joined Conference National side Eastbourne Borough on loan until the end of that season, and made a scoring debut in the 1–1 draw with Grays Athletic. He made his senior debut as a second-half substitute in the 2–1 Football League Cup defeat of Plymouth Argyle and marked his League bow with a goal in the 3–0 win over Exeter City. Soon after he doubled his tally for the campaign with a curling strike from the right edge of the box against Southampton at St Mary's Stadium. He continued his development throughout the season, making a further 23 league appearances, either side of another loan stint at Eastbourne. The highlight of his campaign was a 25-yard drive which snatched a late point for Gillingham in the 1–1 draw with Torquay United at Plainmoor. The midfielder made a goalscoring start to the 2011–12 campaign, netting Gillingham's second in the 3–0 defeat of Plymouth Argyle at Priestfield before scoring from the spot to clinch a point in the 1–1 draw with Accrington Stanley. His third goal of the campaign came in the 5–2 win at Torquay United in October. In total, Rooney made 20 appearances for Gillingham, scoring three times.
On 6 January 2012, Swindon Town made a 'six-figure sum' offer for Rooney, which was eventually turned down by the Kent-based club. On 16 January 2012 a new undisclosed offer was made and accepted by Gillingham. On 17 January he signed a two and a half-year deal with Swindon. Rooney made his Swindon debut on 21 January 2012 in a league match at home to Macclesfield Town as a substitute, coming on in the 52nd minute. He made an instant impact providing the cross for Paul Benson to head home the only goal of the game. Rooney scored his first goal for the club in the 3–0 win against promotion rivals Crawley Town. Rooney joined Crawley on loan until January 2014 on 6 August 2013. Following the completion of this loan, he joined Maidstone United on non-contract terms.
On 21 March 2014, Rooney joined Luton Town on a contract until the end of the 2013–14 season. He played in six games as Luton won promotion to the Football League. In July 2014, Rooney signed a six-month contract extension with Luton. After playing in 12 games, scoring five goals, Rooney's contract was extended until the end of the 2014–15 season. However, he only played in only one more game before his contract was mutually terminated in March 2015.
