Collingwood's Mason Cox has apologised for bumping a GWS assistant coach on the field before their AFL Opening Round clash on Saturday.
Cox ran into former Geelong, Sydney and GWS ruckman Shane Mumford during a warm-up drill on the field before the Giants' 32-point win at the Sydney Showgrounds.
The AFL asked Collingwood to explain what happened, with the club saying Cox was completing a rucking drill and asked for one more bounce from the umpire as GWS started its warm-ups in the centre circle.
It was then that Cox ran through and bumped Mumford, who was holding a ruck pad for his players to practice on.
The American apologised for the contact.
"In the moment, I was solely focused on getting one more bounce in," he said in a club statement.
"In hindsight, I should have stopped my run-up rather than completing the drill."
Collingwood's general manager of football, Brendon Bolton, said "it was a period of transition in the centre circle" but acknowledged "making contact with opposition officials or players pre-game should be avoided".
The Magpies are still working with the AFL to get to the bottom of exactly what happened.
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