Christensen made his AFL debut with the Geelong Football Club in the second Round of the 2011 AFL season against Fremantle in Perth. He was the club's substitute for the match, he was subbed in late in the third quarter and finished the game with eight disposals, assisting Geelong to an 11-point victory. After his performance in Geelong's Round 18 match against Richmond, he gathered 26 disposals and kicked two goals, he was nominated for the 2011 AFL Rising Star Award. Christensen, was a part of the 2011 AFL Geelong Premiership team who defeated Collingwood. At the end of the 2014 season Christensen was traded to Brisbane. By the end of his AFL playing career he had played 133 AFL games.