BRISBANE Lions midfielder Allen Christensen has left the field after injuring his collarbone in a bone-rattling bump from Carlton veteran Andrew Walker.

Late in the second quarter at Etihad Stadium on Saturday afternoon, both players showed great courage to attack a disputed ball in the Blues' forward line.

Walker collected Christensen with what appeared to be a fair bump that left the Lion groggy and nursing his right shoulder.

Christensen walked from the field with the assistance of trainers, with his arm wrapped in his jumper for support.

He was taken straight to the Lions' rooms for treatment and will not take any further part in proceedings.