For over a minute, the Flyers pinned Daniel Paille , Gregory Campbell , and Shawn Thornton in their own zone. The Bruins couldn’t clear the puck. The flurry only ended after goalie Tim Thomas covered a James van Riemsdyk shot at 8:31 of overtime, allowing Julien to change his lines.

While the shift may not have been strong, it was long.

Fourth dimension Eight minutes into overtime, Boston’s skilled lines were feeling the effects of the ice time. So Julien leaned on his fourth line, used sparingly until then, to submit a strong shift to give their mates a breather.

Pronger is Philadelphia’s version of Chara — a mean, hard-nosed, shutdown defenseman. In Game 1, Pronger had two shots and four blocked shots in 19:45 of ice time. Pronger was on the ice for three of Boston’s seven goals.

The big defenseman missed the first five games of the first round because of a fractured hand. Pronger returned for Games 6 and 7 against Buffalo. Danny Syvret dressed in Pronger’s place.

Pronger sits out Chris Pronger didn’t play last night because of an undisclosed injury. Pronger didn’t finish Game 1 and was unavailable for comment. After Game 1, the Flyers informed local media that Pronger would not comment because he had lost his voice.

McQuaid, who skated only seven shifts for 4:04 of ice time, was belted earlier in the first. At 3:37, Jody Shelley ran McQuaid into the boards and was called for boarding. It was the second time this season Shelley had bowled McQuaid over. During the regular season, Shelley was suspended for two games for hitting McQuaid from behind.

The play resembled the incident in 1995 that left Travis Roy motionless on the Walter Brown Arena ice. Roy, then a freshman at Boston University, tried to throw a check on North Dakota’s Mitch Vig . Roy missed and sailed headfirst into the end boards, breaking his fourth cervical vertebra.

McQuaid tried to throw a check on Mike Richards and missed, crashing headfirst into the end boards behind the Boston net at 17:31. McQuaid remained on the ice for several minutes while trainer Don DelNegro came to his side. McQuaid required help from Zdeno Chara and Milan Lucic to skate off the ice.

McQuaid had spent part of the night at Jefferson Hospital, where he was taken after a frightening first-period incident.

PHILADELPHIA — Last night, as the Bruins flew back to Boston after their 3-2 overtime win in Game 2 of their semifinal series with the Flyers, Adam McQuaid was part of the traveling party. It was a welcome turn after a play that could have had a far darker outcome.

But it was a shift Julien needed from his fourth threesome.

“That’s what we had to do,’’ Julien said. “At one point, you notice your bench is running out of gas. You’ve got to go with your fourth line. They’ve got to go out there and do the job. We’ve had confidence in them all year. It was a matter of them going out there. One time, they were out there against the other team’s top line. There’s no doubt I would have liked a better scenario. But that’s where we were at at that time of the game. You’ve got to believe in those guys. They’ve got to do the job. They kept them off the score sheet. It’s things like that which really help your team win.’’

All season, Julien has never had an issue turning to his fourth line, especially Campbell. In Game 1, Campbell scored a third-period goal. But Campbell was prouder of a second-period block of a Kimmo Timonen slap shot during a pivotal Philadelphia power play.

After all, blocks, hits, and faceoff wins — the less-than-glamorous components of the game — are what the coaching staff expects of its fourth-line center. Campbell may only be earning $1.1 million annually, but he is the kind of player every coach craves to have in his lineup.

“Things like that, the small intangible things, are what I try to focus on,’’ Campbell said. “They might not be noticed by a lot of people. But within the team, they’re important. It’s a role I’m happy to play, especially in the playoffs, when every play is such a big, crucial play. The small plays like the blocks, the faceoffs, things like that are plays I pride myself on.’’

Two-way standout Thomas finished the night with 52 saves. Patrice Bergeron should have been credited with one as well.

Because of a backcheck in the first, Bergeron prevented Danny Briere from making it a 3-1 Philadelphia lead. At the other end, Bergeron then assisted on Brad Marchand’s tying goal.

“What more can you say about Bergy? To me, he’s arguably our best forward since the start of the playoffs,’’ Julien said. “He comes to play every night. He plays hard. He plays hard at both ends. He’s contributed offensively, but without a doubt, he’s our most reliable two-way player. He leads by example. You can tell he’s a committed player this year, and he’s also a good leader in the dressing room, and he’s leading by example on the ice. What you saw tonight is just indicative of how well he’s been playing for us.’’

Fluto Shinzawa can be reached at fshinzawa@globe.com. Follow him on Twitter @GlobeFluto

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