PITTSBURGH -- The Pittsburgh Penguins regained their Stanley Cup-winning captain, and he made an immediate impact. Next up: The return of their Stanley Cup-winning goalie.

Perhaps as early as Thursday night, when the Penguins -- already 4-0-1 at PPG Paints Arena this season, and 4-2-1 overall -- take on the New York Islanders.

Matt Murray, who missed the first seven Penguins games as he healed from a broken right hand sustained during the World Cup, is practicing again and served as Marc-Andre Fleury's backup for the first time this season Tuesday night.

Sidney Crosby, who missed the first six games with a concussion, returned Tuesday to score the Penguins' first goal of a comeback in which they flipped a 2-0 deficit into a 3-2 victory over the Florida Panthers.

Coach Mike Sullivan isn't saying whether Murray will be ready to go against the Islanders, but Fleury started the first seven games, and no doubt the Penguins want to give him a night off soon.

If only to see how Murray has recovered from his injury -- and whether he can sustain his level of play during the playoffs, when he became the most inexperienced goalie to win the Stanley Cup since Ken Dryden of Montreal in 1971.

"I think he's getting close," Sullivan said following practice Wednesday. "Having the ability to back up and seeing the game up close (Tuesday) with the speed (of the game), even though he's on the bench, will help with his timing and inch (him) that much closer to being ready to play."

The Islanders will play the second half of a back-to-back after losing 3-2 to the unbeaten-in-regulation Montreal Canadiens on Wednesday night. They lost three of four to the Penguins last season.

Dennis Seidenberg scored the tying goal for the Islanders in the third period -- one of their 15 shots in the period -- but Shea Weber's power-play goal with 2:57 remaining won it for Montreal.

"The first half of the game we didn't manage the puck properly," Isles coach Jack Capuano said. "I think if you watch that third period, we had plenty of opportunities. Came down to their power play."

The Islanders (3-4) will go from playing a Canadiens team that's off to a 6-0-1 start to one that won the Stanley Cup last season.

Asked if the Islanders learned anything from playing the Canadiens, center John Tavares said, "I think just to realize what's going to bring us success, especially against good hockey teams and teams (that) play a similar style of game to us. They play quick and they transition off the ice."

The Islanders have faced Murray only once -- a 5-0 loss on April 2 that was Murray's first shutout in the NHL.

Whenever he returns, Murray likely will wear a cast on his broken thumb for the time being.

"The bone doesn't fully heal for a long time, but it's healed enough where I can do everything normally and not worry about it. I'll wear the cast while I play," Murray said.

He couldn't have played much better last spring when, after appearing in only 12 regular-season games (going 9-2-1 with a 2.00 goals-against average), he carried the Penguins to the Cup with the steady glove hand of a much more experienced goalie. He went 15-6 with a .923 save percentage and a 2.08 GAA in the postseason.

Fleury is his usual reliable self so far this season, with a 4-2-1 record and a .904 save percentage. But the Penguins likely signaled their course for the future last week when they signed Murray to a three-year, $11.25 million contract that begins next season -- even though Fleury is only in the second year of a four-year deal.

The Penguins can only hope Murray is as impactful from the start -- even if he doesn't return Thursday -- as Crosby was. After a get-up-to-speed first period, Crosby looked himself after that, and Sullivan thinks he's good to go despite his prior concussion history.

"There's no reason (not to think that)," Sullivan said. "I think Sid's going to be fine."

Sullivan made one adjustment during the game, breaking up the HBK line of Carl Hagelin, Nick Bonino and Phil Kessel by shifting Kessel to Evgeni Malkin's line and installing Rust as the right wing on the Bonino line. It's likely that will carry over to Thursday.

"He (Rust) brings speed, he brings energy, he creates a lot of turnovers with his speed," Sullivan said of Rust, who scored both goals in the Game 7 Eastern Conference-clinching 2-1 win over Tampa Bay.