Boychuk/By S. Bradley

With two of their top seven defensemen now on the shelf, and with the bulky, hard-hitting, injury-plagued Pittsburgh Penguins joining them on the TD Garden ice tonight, the Bruins need everyone on their back end to play at a playoff level.

That means they need Johnny Boychuk to replicate what he accomplished Thursday night in the win over Tampa Bay.

For maybe the first time this season, the 2010-11 version of Boychuk was in 2009-10 form — not only passing and shooting the puck with an extra burst of confidence, but throwing his body around with reckless (but legal) abandon. He was credited with a season-high five hits, but probably could’ve received even more. Heck, the hip check he threw that forced Lightning forward Nate Thompson to stagger to the bench and check what city he was in was probably worth double credit.

When Boychuk is at his best, he’s timing his checks so that they have the maximum amount of impact on the opposing player and the momentum of the game. Those plays have been too few and far between for the second-year blueliner in the first year of a two-year deal he earned last season.

“You can’t really go looking for them. They usually come to you and you’ll know when it’s time,” said Boychuk of the big hits. “If you do go looking for it, it usually turns up that the puck’s in the back of the net or a scoring chance. You try not to look for it, but if it’s there you take it.”

And Boychuk finally took it against Tampa Bay. In agreeing that Thursday’s performance was one of Boychuk’s best this season, head coach Claude Julien, who twice in a three-game period made Boychuk a healthy scratch in the middle of last month, said that maybe Boychuk just needed to relax to return to last season’s form.

“Hopefully that was the start of something good,” said Julien yesterday after practice. “I liked his physical play. I liked also just bringing the confidence and everything else he did. He was a really solid player for us [Thursday] night.”

“Sometimes you’ll hear us say that to players that are really feeling the pressure – ‘just go out there and play.’ There are players that struggle sometimes because they overthink everything,” the coach continued. “Sometimes you’ve just got to go out there and relax and just play the game, let it happen. And I think basically what he might’ve done is just go out there and played and everything just came back naturally.”

With just one goal on the season and 18 games remaining, Boychuk will be hard-pressed to match last season’s total of five scores. But he’s increased his odds of equaling that total of late by putting his “dimensional” shot to better use. Over the Bruins’ last five games, Boychuk is point-less but has fired 16 shots on goal — by far his best five-game stretch of this season in that department.

There’s no doubt that the opportunity to watch some games from the press box helped Boychuk gain some perspective.

“It’s just focusing a little bit more and probably using those games that I was watching just to learn and to use it for some drive,” said Boychuk, who has totaled 10 points and carries a plus-11 rating into tonight’s game.

While their players are pretty much known for being fearless, the Penguins will at least have to think twice about crossing the blue line or cutting to the middle, if Boychuk is back on his game tonight at the Garden.