PITTSBURGH — Sidney Crosby is used to change. More than 15 years in the NHL has taught the Pittsburgh Penguins longtime captain that it’s simply part of the business.

Not all change, however, is created equal. Having a teammate traded, sign with another club or incur a long-term injury is one thing. Having the architect who put together a roster that led the Penguins to consecutive Stanley Cups resign without warning is another.

So, yes, it was weird for Crosby and the rest of the Penguins to learn after practice Wednesday that general manager Jim Rutherford decided to step down. Rutherford cited personal reasons and declined to get into specifics with anyone, including Crosby.

“I think everyone was surprised,” Crosby said Thursday, several hours before the Penguins lost 4-1 at Boston.

Still, Crosby believes the contribution Rutherford made to one of the NHL’s premier franchises and the state he left it in leaves the Penguins in decent shape, at least after the initial shock wears off.

“I think there’s some great people here that will continue to do good work,” Crosby said.

Patrik Allvin gets the first crack at picking up where Rutherford left off. A longtime member of the scouting department before becoming assistant general manager in the fall, the 46-year-old becomes the first Swedish-born NHL general manager. Not that he’s had time to let the significance sink in.

“It’s definitely been a roller-coaster here, for sure,” Allvin said. “A lot of emotions. A lot of mixed feelings.”

Allvin takes over a team that’s survived a series of injuries — particularly on defense — to work its way into the middle of the pack of what will be a crowded and competitive East Division. The Penguins are 4-3-1 despite losing defensemen Marcus Pettersson, Brian Dumoulin and Juuso Riikola for an extended period in a truncated 56-game season.

While team president David Morehouse is plunging head-first into finding Rutherford’s full-time successor, there’s no telling how long that might take. There are still more than 10 weeks until the trade deadline, but Rutherford developed a reputation for not waiting when he saw a need to be addressed. Even in the hours before he left, Rutherford signed veteran defenseman Yannick Weber to give Pittsburgh a boost at the blue line.