PHILAELPHIA --There was not a specific hit that caused Sidney Crosby 's latest medical issue, according to Penguins coach Dan Bylsma .
And neither is it clear what will have to happen for Crosby to return to the lineup.
Nonetheless, Bylsma said Thursday, there is "no indication of a concussion at this point in time," even though Crosby complained of a "slight headache" after participating in practice Wednesday.
When that happened, team officials decided to hold Crosby out Thursday night in Philadelphia and Saturday against the New York Islanders, even though Bylsma said a neurocognitive test yielded results identical to those produced when Crosby got clearance to resume playing after missing 61 games because of a concussion.
Although Crosby had a collision with Boston center David Krejci Monday, Bylsma said it was "not a one-time incident in the game" that caused his problem. "He took a couple of hits in the game and didn't feel 100 percent after the game."
Crosby, who did not practice Tuesday, visited concussion specialist Michael Collins and took an ImPACT examine that apparently did not detect a problem. Still, he was left in Pittsburgh after informing team officials of his headache Wednesday.
"[Crosby] knows his body well -- he spent a long 10 months [recovering from a concussion] -- and, as a precautionary [measure], is just taking [Thursday] night's game off, and through the weekend," Bylsma said.
He added that, after resting yesterday, Crosby planned to work out today.
Although Crosby has not been made available to reporters since it was announced he would sit out the two games, he spoke about his status on the team's website.
"I just want to be smart with this," he said. "It's been a long road back, and we want to err on the side of caution.
"I've taken some good hits over the past few weeks and am happy with the way my body responded ... but after discussing things with doctors it was better to make sure I was cautious before returning to play."
Crosby's absence forced Bylsma to reconfigure his forward combinations, and center Joe Vitale 's role might have been upgraded more than anyone else's.
After being a healthy scratch four times in a recent seven-game stretch, Vitale was penciled in on a line with Matt Cooke and Pascal Dupuis , the latter of whom is Crosby's frequent linemate.
"I played with those guys at the beginning of the year, when Sid obviously was out and [ Evgeni ] Malkin was out," Vitale said. "I'll just try to keep my game simple, keep it the same way.
"I think [changing my style] would be wrong to do. I don't think anyone is expected to do that. I think everyone knows how each other plays. We feed off each other. ... Once you know how everyone plays, you just play to their strengths."
Richard Park , who got an apparent leg injury late in the Penguins' 3-1 victory Saturday at Carolina, skated briefly before their game-day skate at the Wells Fargo Center, but did not go back on the ice after that.
Crosby had 12 points in eight games after sitting out 61 and, given his history against the Flyers -- 26 goals and 36 assists in 36 regular-season games -- the Penguins certainly could have used him Thursday night.
It's possible that the three defensemen the Penguins played without -- Zbynek Michalek , Deryk Engelland and Kris Letang -- were missed even more, because all are comfortable in the kind of physical, aggressive game the Flyers generally play.
Philadelphia has some big forwards who are not shy about going to the net, and a lot of the veteran toughness on defense simply was not available for the game.
Engelland, though, was on the ice with his teammates at the morning skate for the first time since being injured and has not been ruled out of the game on Long Island yet.
The Penguins activated left winger Steve MacIntyre from the injured-reserve list and put Michalek on it, retroactive to Nov. 26. ... Goalie Brent Johnson missed the game-day skate because of illness but was able to back up Fleury.