Krug made his NHL debut/Photo by D. Hickling

BOSTON — Playing in the first of three games that are basically glorified exhibitions because of their locked-in status as the No. 2 seed in the Eastern Conference, the last thing the Bruins wanted to happen tonight against Pittsburgh was an injury to a key player.

Well, their worst nightmare became reality when Johnny Boychuk went down to the ice after a collision with Penguins forward Arron Asham 6:45 into the third period of Pittsburgh’s 5-3 win at TD Garden.

Boychuk had stepped up on the attack when the two players came together leg-on-leg. After getting checked out by trainer Don Del Negro, Boychuk had to be helped off the ice. Now the Bruins will await word on their important second-pair blueliner.

“Well, those kind of injuries, you’ve got to kind of let the night go by and the next day you get a better idea,” head coach Claude Julien said. “We’re keeping our fingers crossed right now that it’s not bad news, so that’s all we can hope for right now.”

Boychuk was seen limping out of the Garden under his own power after the game.

Sidney Crosby’s two goals, including one during a questionable 5-on-3 power play, helped the Penguins better their chances at the No. 4 seed in the East with the win. Rich Peverley’s high-sticking penalty after Daniel Paille’s charging violation put the Penguins up two men. The Peverley high stick was questionable at best because replays showed Peverley’s stick barely grazed Kris Letang’s shield-covered face.

“You know I didn’t think I got him but the refs thought so, but what can you do about it now?” Peverley said.

Peverley scored his first goal in his sixth game since returning from a knee injury.

▪Defenseman Torey Krug, just a week removed from playing for Michigan State, made his NHL debut. He skated 18:18 of ice time and landed two shots on net while skating a regular shift next to Boychuk.

“Yeah it was great, getting up and down the ice, the one main difference here is every player can make a play and there’s no shifts off and that’s the biggest difference,” Krug said.

▪Giving Tim Thomas a full night out, Marty Turco started in net and was backed up by Anton Khudobin. Turco stopped 22 of 27 shots in what was probably his last game with the Bruins.

“It’s been tremendous, really,” said Turco, who plugged a big hole in the Bruins after Tuukka Rask was injured last month. “I’ve been around for a bit; can’t say that disappointments have been much a part of my time here. I’ve been fortunate to have an opportunity and I’m truly grateful, for my family and I, for [what] the Boston Bruins gave me when things seemed pretty bleak. You want to play great and you want to show them, never mind anyone else, and for the most part – days, game and practice, and being a good team man – I’ve felt pretty proud of my time here so far. Between Tampa and a little bit tonight, those two games – part of them anyway – are pretty disappointing but at the end of the day I’ll continue to hold my head high like I have all year to be ready in this position and still want to play some. So, we’ll see what happens.”