OTTAWA -- After allowing three power-play goals in the first two games of the Eastern Conference Semifinals against the Pittsburgh Penguins, the Ottawa Senators' penalty kill came up big when it was needed most.

Against perhaps the finest collection of talent in the NHL, the Senators went a perfect 6-for-6 on the penalty kill -- and scored the game-tying shorthanded goal -- in a 2-1, double-overtime Game 3 win Sunday night.

"I think when you play teams numerous times you start to learn their tendencies. With Pittsburgh it's hard to learn their tendencies because they have a lot of talent on their power play," said Colin Greening, who was the overtime hero after captain Daniel Alfredsson tied the game with 28.6 seconds remaining in regulation time. "We still have lots to learn in terms of the PK, but I thought we were successful tonight.

"To be honest, that's what we're going to need if we're going to be successful against them, is to be able to shut down their power play."

The Senators trail the best-of-7 series 2-1 with Game 4 at Scotiabank Place on Wednesday (7:30 p.m. ET; NBCSN, CBC, RDS).

The Penguins spent a significant amount of time working on their 5-on-3 power play at Sunday's morning skate, but it didn't help them when they had 58 seconds up two men early in the second period, mustering two shots on goal.

As is often the case, Ottawa's goaltender was its best penalty killer, with Craig Anderson making 12 of his 49 saves when Pittsburgh was on the power play.

"Andy's been stellar," said Senators defenseman Marc Methot, a key component of the penalty kill. "I just keep repeating myself over and over, but he's been our team's MVP."

Alfredsson scored the tying goal while technically shorthanded after Erik Karlsson was called for slashing at 18:33 of the third period, but the Senators had five players on the ice after Anderson was removed for an extra skater. The Penguins had 33 seconds of power-play time to open the first overtime period and had a power play in the second overtime yet came up empty.

"We've struggled the last couple of games against them," Methot said. "We wanted to be a lot more aggressive, I don't know if we were, but it seemed like we had more success tonight.

"It discourages a team when they don't get things going early, especially when you have a talented group like that."

That ability to plant a seed of doubt in the Penguins' minds had the opposite effect on the Senators, who have proven something important to themselves: They can go toe-to-toe with one of the top teams in the NHL.

"It shows that we belong here and we can hang in with these guys," Methot said. "I think we needed that."