OTTAWA -- The Philadelphia Flyers have had a hard time holding third-period leads this season, and after their most recent fiasco, they were determined not to let it happen again.
Philadelphia won for just the fourth time in seven games it has led after two periods this season. The Flyers gave up five third-period goals Friday in Carolina to blow a 5-3 lead.
"We kind of left that arena disgusted with ourselves a bit and found it a long flight home," Knuble said. "We've found ourselves in that position a lot of times so far, with a good lead going into the third. Tonight we added another goal and hung on there, so it was something that we had talked about and wanted to make sure we did right."
After Zdeno Chara tied it at 2 with two straight goals, Philadelphia went back ahead on a power-play 14:52 into the second when Knuble was credited with his fifth goal of the season. The Flyers went up 3-2 as Eric Desjardins' point shot apparently struck Knuble after it deflected off Senators forward Chris Kelly on its way past goalie Dominik Hasek and into the net.
"I don't think I even touched it," Knuble said. "Unless they saw something I didn't feel, I can't say I touched it."
"It was a great effort by our team," Gagne said. "We had the lead in Carolina and we found a way to lose that game a couple of nights ago. We were in the same situation tonight and I think we played a pretty strong game for 60 minutes. It was a huge win for us here in Ottawa."
Chara also assisted on Wade Redden's goal for Northeast Division-leading Ottawa, which won 8-0 in Toronto one night earlier.
"Last night everything we touched went in the net, and tonight it was tougher to put them in, but you can't make any excuses, we took too many penalties, we weren't skating as much and they took the play to us early on," said Senators center Jason Spezza, who assisted on Chara's second goal.
Sim scored Philadelphia's third power-play goal of the game at 19:40 of the second period to make it 4-2. Knuble made it a three-goal lead 1:14 into the third.
"That was the difference really in the game, the second period," Senators coach Bryan Murray said. "We had battled back, we didn't look very sharp in the early going, then we kind of played ourselves back into the game and then the power play for them did us in."
Hasek, who recorded his second shutout of the season against the Maple Leafs, lost for just the second time in eight starts as the Senators suffered their first loss in five home games.
Carter opened the scoring at 9:20 of the first period and Gagne made it 2-0 at 14:52, just eight seconds after Ottawa captain Daniel Alfredsson was sent off for hooking.
Chara drew the Senators within 2-1 with a power-play goal at 17:37.
The 6-foot-9 defenseman tied it with a similar effort 7:16 into the second. He got his third point of the game as Ottawa drew to within two midway through the third, combining with Alfredsson to set up Redden's fifth of the season on a power play at 9:58.
- Flyers D Kim Johnsson did not return after leaving the game because of a left groin strain in the first.
- Forsberg has 17 assists and 19 points, both team highs.
- C R.J. Umberger made his NHL debut for Philadelphia. The Pittsburgh native was recalled from the Philadelphia Phantoms of the AHL earlier in the day.
- Senators RW Dany Heatley, who tied a team record with four goals Saturday, assisted on Chara's first goal to extend his points streak to 10 games.
- Flyers captain Keith Primeau did not play. Primeau was injured in Tuesday's loss in Montreal, but did play in Philadelphia's 8-6 defeat to Carolina on Friday.