AFC Bournemouth have signed Christian Atsu from Chelsea on a season-long loan deal.
Midfielder Miguel Pallardo has signed a new one-year deal with newly-promoted Hearts while Danny Wilson leaves.
The 21-year-old has only made one appearance for City, as a substitute against Bolton in the Premier League in May 2011.
He has previously spent time on loan with Ipswich, Oldham and Blackpool.
During his time at Boundary Park last season he scored the winning goal against Liverpool in the FA Cup fourth round.
Wabara has represented England at Under-20 level.