Charlie McAvoy did not play in the third period of the Bruins’ win over Toronto on Thursday with an upper body injury. Karl B DeBlaker/Associated Press

BOSTON — Coach Jim Montgomery said the Boston Bruins were being cautious when they shut down Charlie McAvoy for the third period with an upper-body injury, in the Bruins’ 2-1 overtime win over Toronto on Thursday at TD Garden.

McAvoy left the game after a collision with Patrice Bergeron in the second period and did not return.

“Just precautionary,” Montgomery said. “We don’t think it’s anything serious.”

Montgomery does have a history of hopeful optimism as he originally thought the injury that put Taylor Hall on long-term injured reserve wasn’t serious.

Montgomery said he didn’t expect McAvoy to play in either game this weekend. The Bruins host New Jersey at 8 p.m. on Saturday and are at Philadelphia on Sunday. Boston has already secured the best record in the NHL and the start of the playoffs is less than two weeks away.

McAvoy, who is a key part of the Bruins power play and penalty kill, played 14 shifts for 11:58 before going down. He is second on the team in overall ice time and was averaging 23 minutes, 34 seconds per game coming into Thursday’s contest.

The Bruins already had four would-be regulars on the shelf with the playoffs not far off as Derek Forbort, Nick Foligno and Hall have all been out, and David Krejci was out of the lineup Thursday. Hall could be back as soon as this weekend and Foligno has begun skating.

DAVID KREJCI SAT out his second straight game with a lower-body injury on Thursday, a streak that’s expected to stretch to four games on the shelf this weekend.

After Boston’s win Thursday night, Montgomery said the veteran second-line center won’t suit up for either of the team’s games this weekend.

“He’s got some real soreness right now,” Montgomery said. “We want to make sure everyone is feeling really good. When you have some soft tissue, you don’t want to get to the point where it’s chronic.”

Krejci has 16 goals and 40 assists in 70 games this season.

Without him in the lineup, Pavel Zacha moved to center on the second line with Tyler Bertuzzi moving up to the left with David Pastrnak.

Hall, who hasn’t played since Feb. 25, could potentially come off long term injured reserve and play this weekend.

THE THREE PRIMARY teams in the Eastern Conference wild-card picture each won on Thursday, leaving the Bruins with no added clarity about their likely first-round opponent.

With the best record in the Eastern Conference and the NHL sewn up, the Bruins are guaranteed to face the second wild-card team. If the standings hold, Boston would play the New York Islanders when the playoffs begin – likely on April 17.

Mathematically, there are four teams that could be the No. 2 wild card, including Florida, Pittsburgh and Buffalo. Realistically, it’s probably three as Buffalo has a lot of work to do to get in playoff contention.