Eking out the win merely kept them close to the teams just ahead of them in the battle for eighth in the East.
There was a 15-minute delay to begin overtime while paramedics treated a fan in the third row from the side boards who suffered a heart attack after Pittsburgh’s Ryan Whitney scored with four seconds remaining in the third period.
Tomas Kaberle sifted a long shot through traffic past Marc-Andre Fleury 3:55 into extra time to win it for the Leafs.
Toronto remained ninth with 87 points, while Montreal edged Buffalo 4-3 to retain for now the eighth and final qualifying spot with 88. The Leafs have four games remaining and the Canadiens three.
Chad Kilger, Alexei Ponikarovsky, Bryan McCabe and Kaberle supplied the Leafs’ goals during regulation time in front of the largest crowd in franchise history – 19,649. It was their seventh straight home win. They improved to 6-2-2 in their last 10, yet they remained ninth.
Gary Roberts, Maxime Talbot and Sidney Crosby also scored for Pittsburgh.
Kilger opened the scoring at 4:28. After a giveaway by Evgeni Malkin, Jocelyn Thibault stopped a Kyle Wellwood shot and the puck dropped behind him into the crease. Kilger slid it into the open net for one of the easiest goals of his career and his 14th this season.
Roberts tied it at 6:54 on a power play. Bates Battaglia was off for tripping when the former Leaf raised his stick knee high to deflect Sergei Gonchar’s slapshot from the point past Andrew Raycroft for his 18th of the season, and his fifth in 16 games since being acquired by Pittsburgh from Florida.
Toronto, ranked 27th in penalty killing, had to avoid the penalty box to have a chance. In winning the three previous meetings, Pittsburgh outscored Toronto 18-8 and got 14 of its goals on power plays.
Ponikarovsky put Toronto ahead 2-1 at 18:30 when he redirected in a cross-ice Nik Antropov pass for his 20th goal.
It was looking good for the Leafs: they were 18-3-3 when leading after one period prior to this one.
Kaberle made it 3-1 at 3:08 of the second period when he blasted in a low slapshot from the blue-line for his 10th of the season.
Alex Steen got a breakaway seven minutes later and shot into Thibault’s right leg pad.
McCabe made it 4-1 at 11:49 on a power play. Brooks Orpik was serving a hooking penalty. Thibault stopped a Mats Sundin shot and McCabe slammed in the rebound for his 13th goal.
Pittsburgh coach Michel Therrien signalled Fleury to don the mask and replace Thibault, who allowed four goals on 20 shots.
The Leafs were in total control – until Michel Ouellet served up a pinpoint cross-ice pass that Talbot redirected past Raycroft at 16:31 of the second period. His 12th of the season made it 4-2 Leafs.
When the second period ended, it was still looking good for the Leafs: they were 26-3-4 when leading after 40 minutes.
The Leafs survived a minute-long, two-man disadvantage early in the third.
The Penguins upped the pace. Battling with New Jersey for first in the Atlantic, they didn’t want to leave Toronto without a point.
Crosby shovelled in a rebound as he was falling to the ice with 4:38 remaining, setting up a nailbiter of a finish. It was the NHL scoring leader’s 36th goal and 117th point.
A hooking penalty to Josef Melichar 22 seconds after Crosby’s goal stalled the Penguins’ momentum, but they soon turned it on again and, as the final seconds ticked away, Whitney blew a slap shot past Raycroft for his 14th goal.
The Leafs play the Rangers in New York on Sunday, are at home against Philadelphia on Tuesday, go to Long Island to skate against the Islanders on Thursday and are at home against Montreal next Saturday.
Notes: Toronto outshot Pittsburgh 37-26. . . On power plays, Toronto was 1-for-4 and Pittsburgh 1-for-6 . . . Raycroft’s 36th win moved him within one of the single-season franchise goaltending record set by Ed Belfour in 2002-2003 . . . Sundin went an eighth straight game with a goal and remains one back of Darryl Sittler’s club-record 389. Sundin has only one goal in his last 16 games . . . Jeff O’Neill was a healthy scratch for the fourth game in a row . . . The previous attendance record was 19,646 for a 2004 playoff game against Ottawa, and the previous high this season was 19,620 for a Feb. 10 game against Pittsburgh . . . Pittsburgh had won four in a row and nine of its previous 11 before facing the Leafs.