Jack, who can play across the midfield or even in defence, is the son of former Wimbledon and Sheffield United striker Alan Cork and has been a Chelsea player since his his early teens having been picked up by their Academy. Since then, he has developed and spent most of the time out on loan but has remained a regular throughout the international development system over the years.
In recent seasons, he has clocked up a significant number of League appearances for the likes of AFC Bournemouth, Scunthorpe United, Southampton,Watford, Coventry City and Burnley, where he featured in the Premier League, and has also secured a regular place in Stuart Pearce's Under-21 squad.
Jack’s England career started with a debut for the U16s against Northern Ireland in 2004 and he has also played for the U17s, U18s, U19s and U20s before he reached Under-21 level with a substitute appearance in the friendly against Czech Republic at Bramall Lane on 18 November 2008, when he replaced Fabrice Muamba.