Boston's win streak ends at three despite a season-high 46 shots against 36 by the Penguins.
The Bruins will look to get a new streak going with another matinee on Monday, when they host Carolina in the front end of a home-and-home series with the Hurricanes.
Third Period, 18:40, Penguins 3-2: Rask is out for the extra attacker.
Third Period, 16:56, Penguins 3-2: Horton with a bid in front off a nice play by Marchand in the midst of the line change, but Horton lost his stick after the shot and couldn't make a play on the rebound.
Third Period, 13:42, Penguins 3-2: The Bruins threaten again with a wild scramble in front of the Penguins net, and things get nasty after the whistle with Savard and Horton both involved in shoving matches.
Third Period, 12:55, Penguins 3-2: Ryder with a bid for another goal as he breaks in at the left post off a cross-ice pass from Savard.
Third Period, 11:30, Penguins 3-2: Rask scoops up a shot from Chris Conner from the left circle. There's been no shortage of shots in this one, with the Bruins holding a 38-35 edge.
Third Period, 9:50, Penguins 3-2: Marc Savard is back out for his regular shift with the top line, seemingly having avoided any injury on that scare.
Third Period, 7:10, Penguins 3-2: Marc Savard is down and hurt in the right corner of the Pittsburgh zone, but is able to skate off on his own power after being tended to by the trainer.
He was hit into the boards by Engelland. No penalty on the play and Savard stayed on the bench and did not have to go to the locker room.
Third Period, 4:39, Penguins 3-2: The Bruins with another giveaway, this time by Boychuk, who puts the puck on Dupuis' stick in front, and Dupuis beats Rask, but it clangs off the right post.
Third Period, 3:25, Penguins 3-2: The Penguins pull back ahead on a goal by Jordan Staal.
Cooke sent the pass out from behind the Bruins net and it hit off McQuaid and bounced to Staal in front, where he backhanded it past Rask.
Third Period, 0:30, 2-2: Nathan Horton with a bid early in the third from the right circle turned aside by Fleury. The top line of Savard, Ryder and Horton has been much more active and effective in this one for the Bruins.
Third Period, 0:00, 2-2: The third period is under way here at the Garden. The Bruins are 2-3-2 when tied after two, but have outscored opponents 55-24 in the third this year. Pittsburgh is 8-2-3 when tied after two periods.
Second Intermission Notes: The Bruins started their rally in the second with two goals 13 seconds apart, but they'll still need a big third period to out the victory in this one.
And they'll have to do it without Steven Kampfer, who is out after taking a high stick early in the second. That's on top of already having Andrew Ference and Mark Stuart out with injuries. Matt Bartkowski has only played six shifts for 4:49 so far, while Zdeno Chara has logged 18:02 already.
The Bruins continue to cough up the puck too much, with 12 giveaways to Pittsburgh's two. That's led to some breakaways and odd-man chances for the Penguins, but Tuukka Rask has come up big to keep this one even.
End Second Period, 2-2: The Bruins didn't wait until the third to rally this time, scoring twice in the second to pull even heading into the final frame.
Second Period, 17:36, 2-2: The Bruins with another chance as Ryder broke in down the left wing on a2-on-1 with Horton. Ryder took the shot himself but it sailed wide.
Second Period, 15:05, 2-2: The Bruins have just announced that Kampfer will not return in this game after suffering an injury on that high stick earlier this period.
Second Period, 11:41, 2-2: The Bruins pull even with a second goal just 13 seconds later, as Michael Ryder fires in a wrister from the left circle.
Savard and Seidenberg get the assists on that one.
Second Period, 11:28, Penguins 2-1: The Bruins get on the board as Dennis Seidenberg blasts one in from the left point.
Excellent work by the fourth line on that shift, with Campbell and Paille providing the screen in front. Thornton and Campbell pick up the assists on the goal.
Second Period, 9:13, Penguins 2-0: Bad giveaway by Mark Recchi to Engelland at the blue line, and Engelland in turn finds Malkin on a long outlet pass for a clean breakaway, but Rask makes the save.
Second Period, 4:57, Penguins 2-0: The Bruins come up empty on the four-minute power play, and remain behind 2-0.
Second Period, 0:57, Penguins 2-0: Dupuis finds another way to hurt the Bruins, cutting Steven Kampfer with a high stick. It's a four-minute double minor for Dupuis, while Kampfer goes off for repairs.
Second Period, 0:41, Penguins 2-0: The Penguins double the lead with a goal by Pascal Dupuis.
Zbynek Michalek's point shot was deflected wide, but Dupuis popped in the rebound off the end boards at the left post.
Second Period, 0:00, Penguins 1-0: And the middle frame is under way, with the Bruins looking for another rally against Pittsburgh.
First Intermission Notes: The Bruins came out strong but couldn't convert their early chances, while Pittsburgh struck midway through the first and poured it on late.
Tuukka Rask had to make some big saves late as the teams finished even in shots at 12-12 after Boston had a 9-3 edge through 14 minutes.
The Bruins have been feisty, with Brad Marchand sparking a scrum with a big hit on Evgeni Malkin, Adam McQuaid dishing out some good shots, Johnny Boychuk getting after Matt Cooke and Greg Campbell duking it out with Craig Adams. But Boston has also been a bit sloppy with the puck, with five giveaways to none for Pittsburgh. Two of those giveaways were by Tyler Seguin.
Boston does have a 12-8 edge in faceoffs, led by Marc Savard's 7-2 mark. Savard had a strong first period, creating several scoring chances and even getting a little shot in on Cooke in the final minute.
End First Period, Penguins 1-0: The first 20 minutes are in the book, and the Bruins will need another comeback against Pittsburgh as the Pens grabbed a quick 1-0 lead.
Savard got in a little shot on Cooke in the final minute. With Cooke crashing the net for a rebound, Savard reached in from behind to give him a swat in the back of the head and a bit of a face wash. It's far less than what Cooke deserves for what he did to Savard last year, but still enjoyable to see.
First Period, 17:59, Penguins 1-0: Boychuk and Cooke get tangled up in the Bruins zone. Boychuk all but begging the pest to drop the gloves, but just as he declined the offer in Pittsburgh on Monday, Cooke refuses to go with Boychuk here.
First Period, 15:10, Penguins 1-0: The gloves come off with Greg Campbell and Craig Adams in a dandy.
Campbell got going late with some big shots, but headed straight for the locker room after the bout. It appeared that Adams' skate may have caught Campbell's hand on the ice that end, but there was also less than five minutes left in the period so Campbell could have been going off just for that reason.
First Period, 15:07, Penguins 1-0: Rask with his best save yet, robbing Dupuis with the glove on a shot from the slot.
First Period, 14:03, Penguins 1-0: The Bruins have a 9-3 lead in shots and an edge in scoring chances so far, but so far Pittsburgh has the only shot that matters for the 1-0 lead.
First Period, 10:57, Penguins 1-0: The Penguins strike first with Cooke beginning the play, coming out of the box and carrying the puck down the right wing.
He sent it over to Jordan Staal on the left, who then passed it to Chris Kunitz in front for the goal. The play was reviewed for a kick as it went in off Kunitz's skate, but the goal was ruled good as there was no kicking motion.
First Period, 10:40, 0-0: That was a power play the Bruins would have really enjoyed scoring on with Cooke in the box, but they come up empty.
First Period, 8:40, 0-0: The Bruins get another power play thanks to Cooke. McQuaid nailed him with a clean hit, and Cooke retaliated with a run at McQuaid, drawing an interference call for the cheap shot.
First Period, 7:20, 0-0: The Bruins kill off that penalty as well, as the game remains scoreless.
First Period, 5:20, 0-0: The Penguins will get their first power-play chance, as Ryder gets called for tripping, negating a potential breakaway for Savard.
First Period, 4:12, 0-0: The Bruins come up empty on that power play, as the sides are back at even strength.
First Period, 2:12, 0-0: Brad Marchand with a big hit on Evgeni Malkin. That draws Pascal Dupuis over, but Adam cQuaid steps in. Deryk Engelland then tackles McQuaid as a scrum develops. Dupuis gets the only penalty for slashing, putting the B's on the power play.
First Period, 1:00, 0-0: Good opening shift from the Savard line, which produced three shots and a couple good scoring chances.
First Period, 0:00, 0-0: And this one is under way, with the Bruins looking to win their third straight over Pittsburgh and fourth straight overall.
12:55 p.m.: Interesting matchup on the opening draw for this one, as Matt Cooke will start at left wing for Pittsburgh and Marc Savard's line gets the call to start for Boston.
Cooke will be joined up front by Jordan Staal and Tyler Kennedy, with Brooks Orpik and Kris Letang on defense and Marc-Andre Fleury in goal.
The Bruins have Michael Ryder and Nathan Horton flanking Savard, with Dennis Seidenberg and Johnny Boychuk on the blue line and Tuukka Rask in net.
12:50 p.m.: The scratches are in, and there was no drama with the Bruins, who have no healthy scrtaches to make with Milan Lucic and Andrew Ference out injured.
Pittsburgh has scratched Sidney Crosby (concussion) as expected, while Ben Lovejoy (illness) and call-up Dustin Jeffrey (healthy) are also out.
12:40 p.m.: The Bruins rolled the same lines in warm-ups they used Thursday against Philadelphia:
The defense pairings stayed the same as well, with Matt Bartkowski sliding into Andrew Ference's spot on the third pair. Expect the Bruins to mix and match throughout the game though with the veterans picking up some extra shifts, but the initial pairings are:
12:30 p.m.: Tuukka Rask and Marc-Andre Fleury led the teams out onto the ice for warmups.
That will be the goaltending matchup for this one as expected.
12 p.m.: The Bruins and Penguins will get an early start with the first Saturday matinee of the season.
There was no morning skate due to the early faceoff time, but Claude Julien confirmed moments ago that Tuukka Rask would get the start in goal.
Milan Lucic (undisclosed) and Andrew Ference (upper body) are out for this one.
8 a.m.: The Bruins welcome Pittsburgh to the Garden for the first time this season, and for a change it's Boston that has the upper hand in the rivalry.
The Bruins have won the first two meetings between the clubs this season. Both of those games took place in the Penguins' new barn in Pittsburgh, and both of them featured dramatic third-period rallies by the Bruins.
Boston scored five unanswered goals in the third for a 7-4 win on Nov. 10. Then on Monday, the Bruins scored four goals in the final 3:23 to stun the Penguins with a 4-2 decision.
The Bruins followed that with a 6-0 destruction of Ottawa on Tuesday and another dramatic third-period rally for a 7-5 win over Philadelphia on Thursday.
"It was definitely a good feeling," Bruins forward Daniel Paille said of the momentum the Bruins have built off the Pittsburgh win. "It gave us some confidence, especially against a team like that, that we could score goals and also defend toward the end. It was really huge for us."
But now they have to prove they can do it again, and do it against a Pittsburgh team seeking to avenge those two losses and climb back into the top spot in the Eastern Conference. The Bruins are in third, and have a right to consider themselves among the elite with this week's wins over Pittsburgh and Philadelphia, as well as three victories over Washington and two against Tampa Bay, including an 8-1 blowout in December.
"I think we're considering ourselves one of the top teams in the East," Bruins forward Patrice Bergeron said. "We've just got to play like we are and play consistent."
Another win over Pittsburgh will be a big step toward that.
"That's the thing," Paille said. "That's a real solid team there with their three big centermen, so we've just got to be ready. We know that we can play with them and come out on top, so we just have to focus on that."
Pittsburgh will be without their top center with Sidney Crosby still sidelined with a concussion, but Boston has injury issues of its own. Lead goal-scorer Milan Lucic remains questionable after missing the last two games with an undisclosed injury, while defenseman Andrew Ference is also questionable with an upper-body injury. Facing Pittsburgh shorthanded will be a challenge, as the Penguins boast a balanced attack even without Crosby.
"They're a good-sized team," Bruins coach Claude Julien said. "There's a lot of character players on that team as well. They've got a good mix of skill and grit and character. To me they're one of the elite teams and they've earned that reputation."
The puck drops at 1 p.m. for the first Saturday matinee of the season, so check back here throughout the day for updates on all the action.