Crosby took the ice for the pregame skate at Nassau Coliseum and stayed out well after the rest of the Penguins went off to the dressing room.
Crosby's sprained right ankle has forced him to miss six straight games and 27 of 30. He said he feels better than he has in some time, but isn't in game condition yet.
"I didn't come in here expecting I would play tonight," he said before the game. "My ankle is feeling pretty good, but I'm just not ready yet."
Although he wasn't set to go Monday versus the also-ran Islanders, the Penguins captain wouldn't say if he would also sit out Tuesday at New Jersey in a key game against the Devils.
With Monday's loss, Pittsburgh stayed two-points ahead of idle New Jersey at the top of the Atlantic Division. The Penguins dropped three points behind Montreal in the fight for first in the Eastern Conference with six games left.
The Penguins have won five of seven, including a 7-1 home victory over the Devils on Saturday night that broke a deadlock for the division lead.
"It's a big game but it's a little bit easier probably not to push yourself when the team is playing so well," he said of Tuesday's matchup. "You have to feel good injury-wise. I have felt a lot better as we've gone along here the last week or so. As long as that continues and I continue to get in shape, hopefully it'll be soon.
"It's felt the best it has in months right now, and that's a good sign."
Penguins coach Michel Therrien called Crosby day to day, but liked what he saw Monday.
"I'm really optimistic," he said. "He looked really, really good."