Western Bulldogs midfielder Matt Kennedy's AFL Wildcard Round night was ended early by a concussion.
He went hard for a footy against Collingwood pressure forward Harvey Harrison resulting in a head clash.
The Dogs otherwise emerged from the night with a clean bill of health.
It was a savage blow for the Dogs, with Kennedy the club's best player on the night until the point he was sidelined with 27 disposals.
It means he will miss the elimination final after the Dogs defeated Collingwood in a cliffhanger.
He was a critical part of a midfield group which got on top of Collingwood.
