 He scored on his first day as a permanent Mansfield player in a 2–2 away draw with York City, and went on to score 56 goals in just 92 appearances for the club in the Conference.After a trial with Championship club Birmingham City in May 2013, Green signed a two-year contract with the club on 3 July 2013.He scored his first goal for the club against Shamrock Rovers during a pre-season tour of Ireland, but was then knocked unconscious in a challenge and received eight minutes of treatment before being stretchered off.