The Canadiens left Thursday for a three-game road trip but they’re down two of their regular defencemen.

Nathan Beaulieu wasn't on the ice for the Habs practice because of a lower body injury but he will take the trip to buffalo.

If Beaulieu can't play, Greg Pateryn, who has been on the bubble since a giveaway in Detroit in early December, draws in.

“It has been tough waiting and going in playing but it’s a matter of keeping it simple and minimizing my mistakes. I’m going to make some, i just have to make sure they're not too costly,” Pateryn said.

Jeff Petry has been put on the injured reserve list and Michel Therrien says he could be gone for a few games, but his absence gives Mark Barberio a chance to continue this recovery season. He's playing his best hockey right now.

“For me it all started in training camp. I just wanted to leave a good impression there and regardless of what happened I just wanted to keep improving as a player and I feel that's what I have been doing,” said Barberio.

The Habs have won three in a row thanks in large part to Ben Scrivens in goal and Tomas Plekanec's line. David Desharnais's line has been stone cold, so the head coach will see if Sven Andrighetto can change the dynamic.

“It's not difficult to change lines. I'm trying to do the same thing – bring my speed and be creative out there and bring some offence, especially create scoring chances,” he said.

There’s no confirmation but Paul Byron will also likely get back in the lineup on Friday as his injury has healed. The Habs’ road trip starts in Buffalo Friday night and finishes with stops in Phoenix and Denver.