Philadelphia, PA (Sports Network) - Mike Knuble's goal 6:40 into the second overtime lifted the Philadelphia Flyers to a dramatic 4-3 victory over Washington in Game 4 of their Eastern Conference quarterfinal.

With several Philadelphia players engaged in a battle for the puck along the end boards, it was finally dug loose by Jeff Carter. He then dished to Knuble in front of the net, where the winger knocked the disc past Cristobal Huet.

Carter had a pair of goals, while Danny Briere also scored in regulation for the Flyers, who have taken a commanding 3-1 series lead. Martin Biron was stellar between the pipes, turning aside 38-of-41 shots.

"It was a physical hockey game and a great hockey game to be a part of," said Flyers head coach John Stevens. "Both teams played hard. There was a lot of speed out there and a lot of physical play, scoring chances and great saves. We're just fortunate we got a win tonight."

Nicklas Backstrom and Alexander Semin each had a goal and an assist, while Steve Eminger also lit the lamp for the Caps. Alex Ovechkin registered a pair of helpers, but was once again neutralized by a contingent of players, while Huet ended with 42 saves.

Game 5 is Saturday afternoon in the nation's capital.

It was Washington that dictated the pace in the third period, clinging to a 3-2 lead until the Flyers finally converted on the power play with 9:59 remaining. This time it was Briere that lit the lamp, as he stationed himself just off the left side of the crease, knocking home a feed from Mike Richards.

Huet was spectacular the rest of the way, though, and the Flyers wasted another power-play chance in the waning moments of regulation.

There was no lull in the first OT either, as both clubs had 11 shots on goal and showed no signs of exhaustion.

When Knuble ended it, though, his teammates came spilling onto the ice to celebrate while Ovechkin and the Caps looked on in disappointment as they suffered their third straight loss.

Ovechkin, who led the NHL in shots during the regular season, took only one during 28 minutes of ice time. The 22-year-old, now officially mired in a playoff slump, has recorded just one goal in the entire series while getting almost no open looks around the net. He had 65 goals during the regular season.

The Flyers got the hot start, jumping on the board just 42 seconds into the contest. Off a Caps turnover deep in their own end, Scottie Upshall corralled the loose puck, dishing to Knuble, who then sent a pass through the slot to Carter. The young forward took a stride toward the crease and backhanded the puck past Huet, making it 1-0.

Washington then converted on a pair of power play goals.

The first came at the 2:41 mark, as a swarm of white jerseys circled the net until Backstrom one-timed Ovechkin's cross-crease feed past Biron at 2:41.

Semin then put Washington on top during a 5-on-3, ripping Backstrom's no-look pass into the top right corner of the net at 12:59.

Philadelphia made it a 2-2 game heading to the locker room, as Carter worked his way in deep and punched Jaroslav Modry's feed into the open net with 1:27 remaining.

Eminger put the Caps back on top 5:56 into the second period, throwing a shot on net from the bottom of the right circle that snuck past Biron.

The Flyers later squandered their fifth power play of the night, and a delay of game penalty on Braydon Coburn put Washington on the man-advantage at the close of the stanza, with 1:23 of power-play time to open the third.