GEELONG star and anti-violence advocate Patrick Dangerfield has expressed his disappointment about the allegations surrounding Dustin Martin.

But the new Cat also said the investigation into Martin must be allowed to run its course.

The AFL and Richmond are investigating an incident on Saturday night involving Martin and an unnamed woman at a Chapel St restaurant.

Martin has already apologised to the woman and admitted he was drunk at the time.

The woman has alleged that Martin threatened to stab her through the face with a chopstick.

"What's been reported is really disappointing - Dustin's actions are really disappointing," Dangerfield said.

"Richmond have put that across in a media release, obviously.

"But at the moment, it's still very much being investigated.

"So until we know all the facts, we can't really hang someone out to dry."

The Tigers have said they hope to end the investigation by the end of this week.

Dangerfield is an ambassador for The Line, a campaign that aims to stop violence in the community and is also a member of the AFL Players' Association Board.