Chris Pronger out of Flyers' opener

Veteran Philadelphia defenseman Chris Pronger sat out the Flyers' season opener against the Penguins in Pittsburgh Thursday night as he continues to recover from offseason knee surgery.

"I think it just needs to get a little bit stronger. I've only had two real practices. Probably need a little bit more of that to play an NHL-caliber game. Really just get it stronger," Pronger said Thursday after a long on-ice session after most of the regulars were done with the morning skate.

Pronger, who will turn 36 this week, admitted there is ongoing pain in his right knee but that he will continue to skate and work out in the hopes of building up strength in the knee.

Pronger had only two full practices as the season approached. He stayed for extra work during the Flyers' morning skate Thursday, as players who aren't in the lineup often do.

Pronger, who is beginning his 17th NHL season, averaged 26 minutes per game while playing in all 82 regular-season games with Philadelphia last season. He also didn't miss a game with Anaheim in 2008-09.

Scott Burnside covers the NHL for ESPN.com. Information from The Associated Press contributed to this report.