Evgeni Malkin scored the only goal for Pittsburgh, which was trying to win back-to-back games for the first time in nearly a month.
Tristan Jarry had 35 saves for the Penguins, getting his first start of the season one day after being recalled from Wilkes-Barre/Scranton of the AHL after the Penguins placed Matt Murray on injured reserve Thursday.
Jarry played well, but had no chance on the game-winner when Nordstrom tipped a pass from Krug into the net to end it.
“I didn’t have to do much more than keep my stick on the ice,” Nordstrom said.
David Pastrnak also had an assist on the overtime goal, getting to a loose puck after the Penguins got caught on an extended shift in the OT and feeding Krug with a cross-ice pass.
“We’ve given ourselves chances and lost a few games,” Pittsburgh captain Sidney Crosby said. “I felt like we could’ve come out of there we two points.
The Penguins lost in OT for the second time in three games and were more upset about the points they squandered than the points they picked up in three straight.
“I don’t really look at it. We’re looking for wins. We have higher expectations,” coach Mike Sullivan said.
Malkin put the Penguins up 1-0 on a power-play goal 6:09 into the second as Boston’s David Krejci sat out a tripping minor. Kris Letang and Phil Kessel assisted on the goal for Malkin, who has a point in six straight games.
DeBrusk tied it for Boston on a slap shot with 6:20 left in the second on a give-and-go with David Krejci. Kevan Miller also assisted.
The Bruins thought they had another goal with 2:35 left in the second, when David Backes raised his arms after trying to squeeze the puck between Jarry and the post, but the referee signaled no-goal. The call was upheld after a lengthy review, drawing the ire of Boston fans who booed the officials a second time when they skated out for the third period.
Pittsburgh got a late power play when Pastrnak was called for delay of game with 9:19 left in the third after flipping the puck over the glass in the Boston zone. Halak gloved a backhand by Crosby with 8:37 on Pittsburgh’s best chance before Pastrnak returned.
“There could have been easily five goals against us. Jaro was huge,” DeBrusk said.
NOTES: Kessel has a point in seven straight games. . Friday was the Penguins’ only visit to Boston this season. . The Bruins were without captain D Zdeno Chara (lower body) and alternate captain C Patrice Bergeron (rib). . The Penguins placed Murray on injured reserve Thursday with a lower-body injury. . The Penguins, who beat Dallas 5-1 on Wednesday, last won consecutive games during a four-game winning streak Oct. 18-27.
Penguins: Host Columbus on Saturday night.
Bruins: Visit the Montreal Canadiens on Saturday night.
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