Although Saturday's showdown in Philadelphia still projects as a spirited affair between the top two teams in the Eastern Conference -- and the latest chapter in a recently compelling rivalry -- the troubling topic of concussions figures to change the tone somewhat.
Two days after the Flyers learned captain Chris Pronger will miss the rest of the season, they'll also continue to play without standout center Claude Giroux as they try to win their eighth straight game and maintain their East lead over the Boston Bruins.
Philadelphia (20-7-3) has played well without its stars, going 9-2-0 since Pronger was sidelined and winning both games since Giroux took an inadvertent knee to the head from teammate Wayne Simmonds last Saturday.
But the team wasn't expecting Thursday's news that Pronger won't play again this season -- including playoffs -- due to what doctors called "severe post-concussion syndrome."
"You can't replace the kind of guy he is," teammate Andrej Meszaros said. "I hope he's going to be healthy as soon as possible and we'll have to find a way to win games without him. We've done a pretty good job so far but that's a tough break."
Pronger helped carry the Flyers to the Stanley Cup finals in 2010, easily leading the team in ice time during a run that included a shocking comeback from a 3-0 series deficit against Boston.
He's dealt with a variety of injuries lately, but he still had 12 points in 13 games this season.
"I think the hard part -- at the end of the day -- to swallow is that he's been shut down for an extended period of time," coach Peter Laviolette said. "Where there was hope, right now there's not."
The Flyers hope Giroux can return, but he's out indefinitely for now.
Giroux has the look of a budding superstar, leading the NHL with 39 points, but Philadelphia has still managed nine goals in two games without him. Meszaros' third-period tally lifted the Flyers to a 4-3 win at Montreal on Thursday, giving them their longest win streak since an eight-game run in January 2002.
The Bruins (20-9-1) know a bit about streaks -- they won 10 straight last month and are 17-2-1 since Nov. 1, recovering from a slow start to pull within two points of the Flyers.
Boston also has plenty of experience with concussions, having seen Patrice Bergeron miss nearly a year in 2007-08 after a hit by then-Flyers defenseman Randy Jones. Marc Savard's career is in doubt due to post-concussion syndrome.
Coach Claude Julien's team also may be without its captain and top defenseman. Zdeno Chara has missed the last two contests with a knee injury, although he practiced Friday.
The Bruins won on back-to-back nights this week without Chara, outscoring Los Angeles and Ottawa by a combined 8-2 despite being outshot 90-51. Tim Thomas made 47 saves in Wednesday's 5-2 win over the Senators.
"We were behind the 8-ball there at the beginning of the season," Thomas said. "It was a tough start for us and tough overcoming that Stanley Cup hangover. We've definitely turned it around."
A season-opening 2-1 home loss to the Flyers was part of that rough beginning, as Philadelphia gained a measure of revenge after being emphatically swept by the Bruins in the conference semifinals. Giroux netted the Flyers' first goal in that game, while Ilya Bryzgalov stopped 22 shots to improve to 5-1-1 with a 1.85 goals-against average versus Boston.
Thomas took the loss, but he's still 14-3-2 with a 2.06 GAA against Philadelphia, including the playoffs.
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