Western Bulldogs midfielder Tom Liberatore is undergoing a series of hospital tests after his heavy knock during the AFL win over Richmond.
Liberatore was taken to hospital by ambulance during Saturday night's game at Etihad Stadium.
Tigers player Jayden Short collided with him heavily in a marking contest during the second term.
Short collected him in the ribs from behind and Liberatore left the field immediately.
Post-match, Bulldogs coach Luke Beveridge was unsure about the extent of Liberatore's injuries.
They are worried about internal damage and Beveridge said an initial test had returned good news.
"(The scan) came back positive, that internally he's okay at this point, but they have to do a number of other ones to make sure he's okay," Beveridge said.
Liberatore missed all of last season with a knee reconstruction.
His latest injury was typical of a tough night for the Bulldogs, who had to withstand a determined challenge from the Tigers before winning by 10 points.
While the result ensures the Bulldogs return to the top four, thanks to GWS and Geelong losing, Beveridge said it was frustrating night.
"I don't think it gets much uglier ... it was a tough one to sit through," Beveridge said.
The coach dragged star forward Jake Stringer in the third term and the old-school tactic worked.
Stringer redeemed his night by returning to the game and kicking four goals in a match-winning performance.
"I don't do that very often, it's a bit of olden-day stuff, really," Beveridge said.
"I sat on the bench a lot when I played, more because the coach was frightened to put me on than getting dragged.
"But he did, he responded quite emphatically."
Marcus Bontempelli also had a massive last term, where the lead changed five times, while Dale Morris and Easton Wood were outstanding in defence.
Beveridge said Jack Redpath's brain fade in the last term, when he played on and botched a straight-forward shot on goal, was one of a string of incidents from the Bulldogs that left the coach scratching his head.
"When it starts to compound, you think 'are we going to come out of this?'," Beveridge said of their many mistakes.
"We were playing at a speed that was maybe a little bit too ballistic and we weren't able to marry our decision-making and our skills with the speed we were playing.
"Hopefully there's a real positive to come out of (the win) - we'll learn from that and find a way to put the 'governor' on and just temper the speed we're playing a little bit more.
"We have to be a bit careful with that - it could have really cost us the game."
Beveridge remains unsure when key forward Tom Boyd, who is serving a club suspension, will return to the senior team.