(REUTERS) — This Ottawa Senators playoff comeback was unlike any they ever had.

Wade Redden’s goal 6:43 into overtime lifted the Senators to a 3-2 victory over the Philadelphia Flyers Tuesday night. Ottawa leads the Eastern Conference semifinal series 2-1. Game 4 of the best-of-seven series is Thursday night in Philadelphia.

The Senators, who had an NHL-best 113 points in the regular season, trailed 2-1 entering the third. They had been 0-22 in playoff games when trailing after 40 minutes.

Philadelphia was 35-0-3 when leading after two periods this season, including 5-0 in the playoffs.

Marian Hossa and Daniel Alfredsson scored two power-play goals for Ottawa. John LeClair and Sami Kapanen scored for the Flyers.

Redden won it with a slap shot from near the left circle that slipped between goaltender Roman Cechmanek’s stick and the near post.

Cechmanek, coming off a brilliant 33-save performance in a 2-0 road victory Sunday night, stopped 24 shots. He stoned Hossa on a breakaway early in overtime. Minutes later, he made another outstanding save on a shot by Karel Rachunek.

Tony Amonte had a breakaway on Patrick Lalime shortly after Cechmanek stopped Rachunek, but he lost control of the puck going for a backhander.

Lalime had 20 saves.

The Senators tied it at 2 on Hossa’s goal just 22 seconds into the third period. He beat Cechmanek with a wraparound backhander for his fifth goal of the playoffs. A holding penalty on LeClair late in the second gave Ottawa the power play.

Kapanen scored his fourth goal of the playoffs, giving the Flyers a 2-1 lead with 7:14 left in the second.

Amonte, standing behind the net, took a pass from Marcus Ragnarsson and sent it to Kapanen, who one-timed a shot from inside the left circle. Lalime stopped the shot with his glove, but the puck bounced high in the air, off Lalime’s back and into the net.

LeClair gave the Flyers a 1-0 lead just 4:35 into the game on his second goal of the playoffs. Jeremy Roenick set it up with a nifty pass to Amonte, who slipped and took a shot while on his knees. Lalime stopped Amonte’s shot, but LeClair, skating in from the bench, tapped the rebound into an empty net.

Alfredsson tied it at 1 during a four-on-three 1:06 into the second. An interference penalty on Claude Lapointe gave the Senators a power play, and Alfredsson scored 24 seconds later. Redden took a slap shot that bounced off Keith Primeau and went right to Alfredsson, who blasted it just inside the near post.

Alfredsson hit the post in the first period on a slap shot after he stripped the puck from Todd Fedoruk.

Lalime made an outstanding skate save on a backhander by Michal Handzus late in the second.

The Flyers lost to Ottawa in the first round last year, scoring a record-low two goals in five games. Philadelphia played the equivalent of nine games — seven games and seven overtimes — in its first-round victory over Toronto.

Ottawa, which beat the New York Islanders in five games in the opening round, has never advanced past this round, losing twice before.

Flyers coach Ken Hitchcock stuck to his promise, dressing enforcer Fedoruk. Angered by what he called “dirty” tactics used by the Senators in Game 2, Hitchcock said he wanted his most physical players on the ice. … Alfredsson has 24 goals in 52 playoff games. … LeClair has 40 goals in 133 playoff games. … Kapanen had four goals in 28 regular-season games after coming to the Flyers in a trade with Carolina. He has four goals in 10 playoff games. … The Flyers had just two shots in the second period, scoring on one of them.