St Kilda's Jake Carlisle could have a nervous wait until Monday afternoon, after his late hit on Richmond forward Jack Riewoldt in the first quarter of their clash on Saturday afternoon.

Just five minutes into the contest, Riewoldt was hit in the head by Carlisle, and looked to be concussed on impact.

He was helped off the field by trainers and sat on the bench for a few minutes, before going down into the rooms.

Riewoldt is currently undergoing a concussion test, but is unlikely to return.