PITTSBURGH -- Penguins forward Steve Sullivan, perhaps more than any other player on the ice, knows what Sidney Crosby will be going through physically in his first NHL game in more than 10 months.
But only Crosby himself knows what will be going through Sidney Crosby's mind, according to Sullivan.
And, for Sullivan, it is how quickly Crosby adapts mentally in his return to the sport he was dominating a year ago that will likely determine how soon No. 87 plays like, well, Sidney Crosby.
There was a Stanley Cup Final feel to the Penguins and Islanders morning skates Monday, with dozens of reporters, a score of TV cameras and bright lights everywhere in Consol Energy Center. As the Islanders' Matt Moulson said, "We usually don't get this kind of coverage. It's exciting."
The hockey world has waited for months and months to see how the NHL's signature star would respond following his concussion layoff. There has been considerable speculation about when he would return and, once he did, how well he would play.
"My road back was more with the body, physically," Sullivan said. "With him, he could do everything on the ice, but mentally in his head he would get a little bit foggy (after practice). But he could skate and work and do everything on the ice. How he felt afterwards was what was stopping him from coming back."
Still, Sullivan's prediction is that Sidney Crosby will be Sidney Crosby again, and soon. Weeks and weeks of practice, starting in mid-September, in which Crosby was at his dazzling best, have convinced him of that.
"He did some crazy things," coach Dan Bylsma said.
"He's always had that special skill set," forward Chris Kunitz said. "We've seen it for months now."
But, Sullivan warned, it takes time for any player to return to peak efficiency following an extended layoff. And these circumstances are different because Crosby hasn't been on a true timetable like that of a player coming off, for example, a knee injury.
Sullivan missed the entire 2007-08 season due to a back injury and also missed half of the 2008-09 season.
"When I was getting back, we could see an end," Sullivan said. "For me, there was time to prepare and be ready; we had set a date for me to come back. With him it was day to day."
And week to week and month to month. The Penguins initially hoped he would be back last season, but Crosby wound up missing the second half of last season, the playoffs and the first quarter of this season.
That's a long time to be out, even for a player who was on pace for the NHL's most productive scoring season in 15 years when he was hurt following hard hits in successive games Jan. 1 and Jan. 5. At the time he was hurt – he hasn't played since Jan. 5 -- Crosby had 32 goals and 34 assists in 41 games. At this very time last year, Crosby was in the midst of a 25-game scoring streak.
Now comes the great unknown: How difficult will it be for Crosby to not think about getting hit in the head?
"We're all going to hold our breath the first time he gets hit," Sullivan said. "That's without a doubt. Everyone is going to kind of wait. Everyone wants to see. Everyone wanted to wait to see (when he was coming) back, now it's wait until he gets hit for the first time."
Crosby is waiting to see himself.
"Anybody that has gone through this would be lying if they said they're not a little anxious to get those first couple of hits in, whether it's giving them or taking them," Crosby said. "But I think after that, things should be pretty normal except for trying to adjust to playing again."
The Islanders told themselves that they had better be ready to hit Crosby, if the situation warrants it, lest they allow one of hockey's most offensively gifted players in decades to be dominant.
"If you're not playing him hard, if you're not finishing your check on him, he can make you look stupid," Moulson said. "He's obviously gone through a whole lot of different tests and seen a lot of doctors and he's been cleared to play, and I think everyone trusts that that's correct. We're going to play him just as hard as we would before any of this happened. Obviously, we're not going to jump and elbow him in the head, just like we wouldn't anyone, but we're going to play him to (NHL Vice President, Player Safety Brendan) Shanahan's rules and play him hard."
Shanahan has been strictly enforcing the NHL's rules against shots to the head, in an effort to lessen the number of concussions and head injuries in the sport.
Now that Crosby is back, there's another question to be answered, namely how quickly will it take him to get back to being the player so gifted that he had won an NHL scoring title, MVP award, a Stanley Cup and an Olympic gold medal by age 22.
"There's no magic number. Everyone is different," Sullivan said. "The first couple of games are adrenaline, you get through it on adrenaline, and then there's that little lull where the wear and tear of a regular season kicks in. For him, (after) having that huge high of coming back, there's going to be a dip. But he's extremely strong mentally and prepares himself like no one other, so his play might not dip as far."
As players on both teams agree, it's simply good for hockey to have Sidney Crosby playing again. And not just in practice.
"Obviously, for the NHL, it's a great moment," Penguins center Jordan Staal said.
"It's obvious we realize the magnitude of this," Islanders center Josh Bailey said. "It's huge. It's great for the game when you're getting your best player back. It's been a long time coming and you never like to see anyone go through what he's gone through. We know how hard he's worked to get back. It's exciting for everyone."