There is concern over Collingwood forward Tim Broomhead, with Dr Rohan White reporting he could be playing with a fractured jaw.
The 23-year-old went off the ground with trouble on the left side of his jaw.
He returned to the ground, but White is still concerned.
"That's okay: we think of Birchall two or three weeks ago, he had a similar injury (and played through)," he said on Triple M at half time.
"If you just watch him, he just keeps touching the left side of his jaw, he keeps grinding his teeth, something's not quite right. He's seen the doc two or three times, they went down to the rooms.
"He could have a little crack there."
White spotted the injury earlier in the match.
"He got a knock with about 10 minutes to go in the last quarter," he said.
"He's really been troubled on the left side of the jaw...he's just talking to (Collingwood sports physician) Chris Bradshaw as we speak, there's a lot of consternation.
"I'm really concerned he's got a little crack (in his jaw), a la Grant Birchall three or four weeks ago.