OTTAWA -- Dany Sabourin came off the bench and stopped Ottawa's potent scorers in a shootout.
Sabourin, who entered midway through the first period after the Senators took an early 2-0 lead, stopped Antoine Vermette, Dany Heatley, Mike Fisher and Dean McAmmond for the win after making 29 saves in regulation.
"He won a shootout for us earlier this year, and even in the third period when Ottawa really started to pour it on a little bit, we got sloppy and he made some big saves for us," said Ryan Malone, who scored twice.
Sergei Gonchar got his seventh goal 7:07 into the third as Pittsburgh overcame a two-goal deficit for the second time in the game to tie it at 5.
"We're resilient," Penguins coach Michel Therrien said. "I don't think we played our best third period -- we gave up some scoring chances that we don't usually give up but we found a way to come back in the game. Our power play gave us a goal, finally, in the third and gave us a chance to come back. It's nice to get a win."
Spezza scored twice and assisted on Heatley's power-play goal 16:15 into the second, which gave Ottawa its second lead of the game at 4-3.
Christoph Schubert put the Senators up 5-3 when he got credit for his second goal of the season 1:04 into the third.
The Penguins, who erased an early 2-0 deficit with goals by Evgeni Malkin and Malone 18 seconds apart late in the first, mounted their second comeback as Malone scored his second of the game -- his sixth of the season -- on a power play at 5:56 to cut the lead to 5-4.
Colby Armstrong got his second assist of the game when he set up Gonchar to draw Pittsburgh even for the second time.
"Basically, a hooking penalty gets them back in the game, 5-4, then they score one right after," said Senators captain Daniel Alfredsson, who had three assists but didn't take part in the shootout after pulling his groin in overtime. "We had our chances to win it, anyway, but we didn't do it tonight."
Spezza hit a post later in the period and was stopped by Sabourin on a 2-on-1 in overtime.
"This one stings because we probably should have won," Spezza said. "I think we outplayed them, but we didn't, so you've got to learn from it."
Malkin hit the outside of the left post moments after Spezza's chance in overtime.
"Every time we play these guys it's pretty exciting," Malone said. "With the offense they have, their team is pretty much the best in the league right now. It was a great character win for us."
Chris Phillips also scored for Ottawa, which lost 4-2 in Buffalo on Wednesday.
The Senators, who haven't lost consecutive regular-season games in regulation since Dec. 19-21, have dropped four of seven (3-0-3-1) after an NHL-record 13-1-0 start.
Gerber made 20 saves.
Sabourin replaced Marc-Andre Fleury after Phillips' power-play goal gave Ottawa a 2-0 lead at 10:55 of the first.
Malkin created his own breakaway to cut the lead to 2-1, racing down the ice from the Penguins' zone to beat Gerber with a quick shot for his ninth goal at 18:07.
Malkin's goal hadn't even been announced when Malone tied it with his fifth goal at 18:25 on a shot from the slot after taking a setup pass from Sidney Crosby, who ended a 19-game points streak one night earlier.
"He created a lot of space and pushed the D back with his speed there and found me in the slot," Malone said. "I told him I'd get one with him sooner or later."
Tyler Kennedy scored the Penguins' third straight goal 8 minutes into the second to give Pittsburgh a 3-2 lead.
Spezza, who scored his second goal of the season 4:56 in, got his second goal of the game -- his third of the season -- 14:20 into the second to tie it at 3.
Heatley restored the Senators' lead at 16:15 with his 11th goal as he beat Sabourin from the slot on a fine setup by Spezza.
- Penguins RW Mark Recchi was a healthy scratch for the third time in four games, including Wednesday's 2-1 loss to New Jersey. Veteran D Darryl Sydor didn't dress for a fourth straight game.
- Fleury stopped two of four shots. "He didn't have a good start and I thought he could have stopped those pucks," Therrien said.
- Recchi and John Cullen set the Penguins' record for fastest two goals on Feb. 16, 1990, when they scored 6 seconds apart in a 3-3 tie at Winnipeg. Paul Coffey and Troy Loney matched that mark six days later in a 4-3 win over the New York Islanders.
- Christensen had his shootout attempt waved off initially by referee Stephane Auger. That call was reversed as a video review clearly showed that Gerber was unable to keep the puck from crossing the line with his right pad.