(Photo: Bridget Samuels) Dennis Seidenberg and the Boston Bruins -- now trailing 3-2 in the best of seven first round series -- face a must win situation following a 4-3 loss to the Washington Capitals in Game 5

BOSTON — Despite recovering from a two-goal deficit, the Boston Bruins battled back to tie things up at the end of the second period with goals from Dennis Seidenberg and Brad Marchand just 28 seconds apart.

Despite losing both Joe Corvo and Patrice Bergeron to injuries, the Boston Bruins persevered with a short bench.

And despite falling behind 3-2 midway through the third on a goal by old friend Mike Knuble (on a Thomas rebound), the Boston Bruins tied it up late in the third with rocket courtesy of Johnny Boychuk that broke an 0-for-14 drought on the power play.

Yet, through all that, the Boston Bruins found themselves on the wrong end of the scoreboard when Troy Brouwer scored on the power play with 1:27 left in regulation — after a questionable hooking call on Benoit Pouliot with 2:15 remaining — and are now on the brink of elimination following a 4-3 loss to the Washington Capitals at the TD Garden in Game 5.

This is not the situation that the defending Stanley Cup champions envisioned going into Game 6 at the Verizon Center in less than 24 hours. But its a hand that they’ve been dealt with as they hope to avoid elimination and extend the series to a Game 7 Wednesday night in Boston.

“Well, we got a game tomorrow at three so there’s no choice but to focus on tomorrow,” said forward Shawn Thornton. “We obviously don’t want to be here, but we’ve been here before and the experience should help. We know we have to focus on one game — and not the big picture — so we’re looking forward to coming back here.”

This isn’t to say that the Bruins were frustrated with a few incidents surrounding Saturday’s game, including the late penalty on Pouliot.

Earlier in the contest, Zdeno Chara was jostling with Jason Chimera in a corner and got an inadvertent elbow to the head, but the officials declined to blow the play dead. A similar instance occurred when Corvo, battling through a long shift, was still limping after blocking a shot and could not get up under his own power. Yet, the officials still didn’t blow the play dead and eventually Alexander Semin took advantage of a de-facto shorthanded situation to give his team a 1-0 lead with his third of the postseason at 11:16 of the middle stanza.

Those events were eerily similar to a couple of situations where Caps players were down on the ice during Game 4. Yet, the officials blew the play dead even when the Bruins had possession in the offensive zone.

“That’s the frustrating part for me,” head coach Claude Julien noted. “We were in Washington last game and twice they had players down in their own end and we had full control of the puck and the whistle was blown right away with no hesitation and today we decided that it wasn’t. So there’s two sets of rules and I know they are different referees, but it’s still the same series, so that was frustrating because they ended up scoring a goal on that.”

That forced the Bruins to deal with a short bench early, but Marchand felt his team dealt with that nicely as they continued to put pressure on Caps goalie Braden Holtby (34 saves) .

“We did a good job,” Marchand said about being down two men. “We responded well and we found a way to put pressure on them so we did alright.”

While the officials did not help the cause, the Bruins knew that they had to dig deep, especially trying to kill off Pouliot’s penalty.

“Every penalty that gets called that late in the game is tough,” said Seidenberg. “We should’ve killed it off, there’s no excuses and at the end it wasn’t enough.”

“That’s hockey, right?” said Thomas, who made 28 saves in the losing effort. “There’s a lot of things that happen over the course of the series that can change the outcome in the end, and that was one of them. But the outcome of the series isn’t over, so we’ll see if it ends up making a difference or not.”

While its easy to point the finger at the officials, the Bruins too had their chances throughout the contest, but squandered some golden opportunities including a couple of posts on shots from Chara and Daniel Paille (on a shorthanded breakaway).

Certainly there were some good things the experienced Bruins can build on — including the power play — going into Sunday. And with their backs against the wall, again, Boston hopes to lean on experience from last year’s Cup run when they dealt with similar circumstances.

“I hope we can rely on the experience from last year,” said Seidenberg. “This is a different year, but we have that in our bag that we can rely on the way we did last year and hopefully we can pull it off again and just play a strong game from the beginning.”