Matthew Tkachuk hit Nicolas Hague with a dirty sucker punch in Game 1

You can’t do that.

Matthew Tkachuk has been an MVP for the Florida Panthers in the postseason with his OT heroics and his instant walk-off celebrations.

But what he did in Game 1 of the Stanley Cup Final as his team was losing to the Vegas Golden Knights on Saturday was absolutely dirty.

In the third period, with Tkachuk’s team down, his teammate Marc Staal held on to Golden Knights defenseman Nicolas Hague after the whistle. With Staal’s arm around Hague, Tkachuk punched a defenseless Hague right in the face.

Is that suspension-worthy? Fans might be wondering. But it was a double-minor for roughing and a game misconduct, so he left the contest.

Either way, this was dirty:

Not good.