Blackett signed for Celtic on Saturday August 29, 2015 to become Ronny Deila’s sixth signing of the summer. The 21-year-old arrived on a season long loan deal from Manchester United and was presented to the Celtic support at half-time during the Bhoys league tie against St Johnstone.
Prior to his arrival at Celtic, Blackett progressed through the academy ranks at United before enjoying loan spells at Blackpool and Birmingham City. Following his senior debut last season, Blackett was called into the England U21 squad, having previously represented his country at every age level.