Pittsburgh coach Mike Sullivan believes his undermanned Penguins can beat any team right now, despite missing five of their top nine forwards.

The Penguins proved it on Wednesday night by knocking off the Colorado Avalanche, the league's last unbeaten team.

Brandon Tanev scored a short-handed goal in overtime and the Penguins beat Colorado 3-2.

"When you have the number of injuries that we have, I think it creates a level of urgency among our group, and these guys have responded," Sullivan said. "They never look for excuses. There's an expectation that we can win games regardless of who's in our lineup and that's how we approach it."

Tanev, Pittsburgh's biggest free-agent pickup in the off-season, spent the first four seasons of his career with Winnipeg, earning a reputation as a quality penalty killer and a hard-working, two-way player who can chip in at both ends of the ice.

Tanev, who set career highs in goals and points last year, scored his first goal with the Penguins at 3:57 of overtime and joined Hall of Famer Mario Lemieux as the only players in franchise history to score an overtime goal while short-handed.

Tanev swooped into the zone and threw a shot on goal that went between Philipp Grubauer's pads. Colorado forward Gabriel Landeskog knocked the puck into the net, giving Pittsburgh its fourth straight win for the first time since an eight-game winning streak last season.

"I saw some open ice and just wanted to get one to the net," Tanev said. "I was fortunate enough to get a generous bounce."

Pittsburgh's Sidney Crosby continued a season-long, seven-game point streak, scoring his fourth goal of the season. Jake Guentzel added to his six-game point streak with his fifth goal in four games. Matt Murray made 26 saves.

The Avalanche, the NHL's last unbeaten team, looked to start the season with six straight wins for the first time since 2013-14. The best start in franchise history came during the 1985-86 season, when the team was located in Quebec and the Nordiques opened 7-0.

Nathan MacKinnon scored his third for Colorado, off an assist from Mikko Rantanen. Both have a six-game point streak to open the season. Matt Calvert also scored, and Grubauer stopped 30 shots.

"I don't think we're happy with the outcome or how we played," Grubauer said. "A couple games ago, we weren't playing great and found a way to get two points. Maybe this was a little bit of a reality check."

Sullivan credited the Penguins' leadership while the team is without so many players.

Jared McCann missed the game with a lower-body injury, forcing defenceman Juuso Riikola to play left wing on the team's fourth line.

Evgeni Malkin and Nick Bjugstad have been out for five games, while Alex Galchenyuk missed his fourth on Wednesday. All have lower-body injuries. Bryan Rust has been out since the start of the season with an upper-body injury.

"I think our veteran guys have really stepped up," Sullivan said. "In some ways, the young guys are helping the veterans by bringing the energy and our veterans are providing leadership and playing the game the right way."

Crosby and Guentzel stepped up early for Pittsburgh.

Crosby evened the score at 17:22 of the first on an individual effort with the teams at 4-on-4. He chipped the puck past Erik Johnson along the boards, worked around Samuel Girard in the slot and backhanded a shot past a fallen Grubauer.

Guentzel gave Pittsburgh a 2-1 lead at 15:30 of the second. He took a pass from Crosby, pulled the puck under Ryan Graves' stick and flicked a wrist shot over Grubauer's shoulder.

"(Guentzel) got a great pass from Sid, but to get the puck under the stick, onto his forehand and under the bar the way he did, that's a goal-scorer's goal," Sullivan said. "It's inspiring the way he plays."

NOTES: Penguins D Kris Letang surpassed Jean Pronovost for fifth on the team's all-time games-played list with 754. Letang's season-opening six-game point streak ended. ... Avalanche D Cale Makar was unable to become the second defenceman in NHL history to begin his regular-season career with a six-game point streak. ... Avalanche F J.T. Compher returned after missing three games with a lower-body injury. ... Colorado didn't score a power-play goal in a game for the first time this season. ... Pittsburgh has seven wins and points in eight of its last 10 home games against the Avalanche.

UP NEXT

Avalanche: Continue a season-long six-game trip Friday at Florida.

Penguins: Host Dallas on Friday.

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