BOSTON — The Bruins’ power play has been red-hot throughout the team’s first-round Stanley Cup playoff series against the Toronto Maple Leafs, but the unit was unable to carry Boston to a series-clinching Game 5 win Saturday night at TD Garden.

The B’s entered Game 5 with the best power play in the playoffs at 45 percent, so you’d think six power plays would be enough to lift Boston to victory. It’s not often a team gets six power plays in one game —  the B’s had 6-plus power plays in just four of 82 regular-season games and just one total PP chance in Games 3 and 4 in Toronto combined.

The Bruins’ PP did score on its first try in the second period when David Backes won a puck battle in front of the net, but Boston’s power play didn’t convert on its next five opportunities.

Toronto’s penalty kill, which hadn’t been good in this series, stepped up in a huge way in the Leafs’ 4-3 win to extend the series.

One of the turning points in the game came in the second period when the Leafs took two penalties in 26 seconds, putting the B’s on a 5-on-3 power play for 1:34. It was a huge opportunity for Boston, and despite getting some good looks, it wasn’t able to find the back of the net.

“(The Leafs) did a better job pressuring us,” Bruins coach Bruce Cassidy said. “I thought we had numerous chances to score, so I’ll give their goaltender credit. The 5-on-3 we had some looks and (Frederik Andersen) made a hell of a save on (Brad Marchand). Our 5-on-3 has been pretty good this year. We tend to look for a seam and get a high-percentage shot. We got a couple that we wanted.”

There’s no reason for the Bruins to be concerned about the power play or make drastic changes to the two PP units — more than enough scoring chances were created. But there’s no question the execution has to be better, especially against a Leafs team capable of scoring four or five goals any night because of its four skilled lines.

“The power play, when you look at the numbers, was 1-for-6, the immediate thing is it’s not good enough, but I thought we generated offense on the majority of them to get goals,’ Cassidy said. “Again, I give their (goalie) credit, but in hindsight, we needed more.”

Here are some other notes from Bruins-Leafs Game 5: 

— Bruins center Patrice Bergeron returned to Boston’s lineup after missing Game 4 with an upper body injury.

“I won’t project past Game 6. He made it through (Game 5) healthy, finished the game,” Cassidy said. “You always want to see how they are in the morning. I don’t anticipate there being any issues going into Game 6. Of course, that could change, but that’s the way it is right now.”

— Bruins forward David Pastrnak did everything except score. He attempted 18 shots, 10 of which hit the net, five were blocked and three missed.

— Bruins goalie Tuukka Rask didn’t play well and was pulled by Cassidy after Tyler Bozak gave Toronto a 4-1 lead in the second period. Anton Khudobin received his first taste of playoff hockey as a result, and he stopped all eight shots he faced.

Rask gave up four goals on 13 shots, two days after he was the best player on the ice for Boston in their 3-1 Game 4 win up in Toronto.

“I didn’t think (Rask) had it (Saturday), so we went with Anton, who’s been very good for us,” Cassidy said about his decision to switch goalies. “There’s always that part of it gets the rest of the team’s attention as well.”

— Bruins defenseman Torey Krug continues to be a scoring machine. After tallying a career-high 59 points during the regular season, Krug has posted another six points (one goal, five assists) against the Leafs, as well as 19 shots on goal.

— Leafs forward Nazem Kadri returned from his three-game suspension and made an immediate impact by assisting on Andreas Johnsson’s first-period goal that put the Leafs up 2-0.

— Just like when the Leafs were trailing 3-1 in their first-round series versus the Bruins in 2013, Toronto came into Boston and escaped with a hard-fought win. And as TSN points out, there are several similarities between the two Game 5s.

Thumbnail photo via Bob DeChiara/USA TODAY Sports