For most of the Bruins, they’ve been in this position before. But on the other hand, they’ve also been in the position the Senators are in.

The Bruins enter Game 5 Friday night in Ottawa with their season on the line. Thanks to their 1-0 loss at TD Garden in Game 4 Wednesday night, the Bruins find themselves down 3-1 in the series.

Winning in the playoffs is one of the most difficult things to do in any level of hockey. Winning that fourth game and closing the series is always more difficult.

If anyone in the Bruins room can tell you how difficult earning that fourth victory is, it’s Patrice Bergeron. The veteran forward saw first-hand how difficult that task is in playoff series like Philadelphia in 2010 and Toronto in 2013.

“You’re disappointed but you have to keep your chins up. I’ve said that – I’ve been in it when you’re up 3-1 and it’s tough to get that fourth win so it’s one game at a time, you keep fighting, keep pushing,” Bergeron told the media following the Game 4 loss.

The Bruins know what they need to do in order to advance to the second round of the Stanley Cup Playoffs. Despite needing three straight wins against a team they’ve only beat once this season, the Bruins know they need to take things one game at a time.

That starts Friday night in Ottawa.

“We have to face reality here and come out with our backs to the wall in their building – these things are taken one game at a time,” said David Backes, who had three shots on goal in 17:40 of ice time in Game 4. “Take care of business in their barn and get it back here and change momentum of the series, that’s our focus now.”

In a series that has produced four one-goal games, the Bruins know that they’re not far off and by no means are they packing it in.

“Get ready and it’s not over until it’s obviously over,” said Bruins’ captain Zdeno Chara. “We know it’s still playable, it’s 3-1, it’s not an ideal position but we know that we can play the same way, even better and get better results.”

As close as the four games have been, picking up a single victory, let alone three, is not going to be easy for the Bruins. There are still several things that they need to fix quickly in order to bring the series back to Boston for Game 6 on Sunday. From their low shot totals to finding an answer for Erik Karlsson and Bobby Ryan to getting production from Brad Marchand and David Pastrnak, the B’s have suffered their fair share self-inflicted wounds through four games.

“I mean you just have to lay it all on the line and go back [Thursday], watch some film, see what we can improve on but like you said it’s win or go home so I think everyone has the right mindset going into Friday and we’re not giving up so we’re ready to take it to game seven,” said Noel Acciari.

With their one game at a time mentality intact, all the Bruins need are a few favorable bounces and they very well could be back in Ottawa for a winner take all Game 7 in six days.