Gilbert began his career at Birmingham City as a trainee but failed to make a first team appearance. He did captain the academy side during his time with the Blues and made many appearances for the reserves. His progress was hampered by a serious knee injury. Once he recovered the decision was made to make a fresh start at another club. He joined Plymouth Argyle at the beginning of the 2003–04 season on loan, where his performances earned him a permanent move. Once he signed, Gilbert soon proved himself to be a reliable and steady player and was a mainstay of Argyle's Second Division championship-winning side, playing 40 league games and scoring one goal against Tranmere Rovers.[3] His only other goal for Plymouth came three days after his goal against Tranmere in a Football League Trophy tie against Bristol City.[4]
This run of form led him to be called up to the Welsh under-21 squad and receiving his first cap. He went on to make 10 appearances in the 2006 UEFA Under-21 Championship qualifying campaign.[5] During this campaign he impressed head coach John Toshack enough to consider him for the senior squad,[6] and was a member of Toshack's senior squad for a six-day training camp in Spain at the end of the 2004–05 season.[7]
However, Gilbert made just six appearances for Leicester before being loaned to fellow Championship side Sheffield Wednesday in November 2005.[9] He joined Wednesday on a permanent basis in 2006 and, following three years at the club, his contract was terminated by mutual consent on 6 April 2009.[10]
After trials with Huddersfield Town,[11]Southend United[12] and Coventry City,[13] Gilbert joined Oldham Athletic on a short-term contract.[14] However, because the player wanted more stability than was afforded by the week-to-week deal with Oldham, he left before the 1 September transfer deadline to allow him the chance to find a permanent club.[15]
On 8 July 2010 Gilbert signed a pre contract agreement with Southend United due to the club being under a transfer embargo, on 6 August 2010 Southend's embargo was lifted allowing Gilbert to be registered with the Roots Hall club. Gilbert had previously played under Southend boss Paul Sturrock at Sheffield Wednesday and Plymouth Argyle.
Gilbert picked up an ankle injury in a pre season game against Derby County which forced him to miss the start of the league season. He finally made his debut for the club on 24 August 2010 against Wolverhampton Wanderers in the League Cup. Gilbert made his league debut in Southend's 2–0 win against Bradford City on 27 August 2010. After a 2011–12 season which ended in playoff defeat, the club did not offer Gilbert a new contract.[20]
After the end of his playing career, Gilbert joined West Bromwich Albion Academy as a coach. Working with various age groups over an eight-year spell – ultimately acting as U18s manager from 2019 to 2022.[26]