In an unexpected turn, unexpected even to Kevin Hayes, the Flyers’ center had to undergo abdominal surgery Tuesday and is expected to miss six-to-eight weeks.

The procedure comes two days before the start of Flyers training camp.

Head coach Alain Vigneault said Hayes felt something in his groin while skating Monday. Hayes underwent an MRI and then had surgery Tuesday morning. Vigneault believes Hayes will miss nine-to-10 games to open the regular season, which begins October 15.

Hayes also had sports hernia surgery in late May. Is this injury related to the previous procedure?

“I’m not quite sure,” Vigneault said Tuesday. “I’d have to talk to the docs and [Flyers director of medical services Jim McCrossin], this happened yesterday and he got operated on this morning. I’m not sure if it was related to what happened last year, but I do now he came out of surgery this morning, docs told Jimmy it went well. Injuries are a part of the game, you have to expect them, that’s why you need depth, that’s why you need players to be ready at all times.”

Hayes has had a lot happen this offseason. He experienced a tragedy off the ice in August with the death of his brother Jimmy Hayes. In regard to Hayes’ second surgery and the setback on the ice, Vigneault said in his conversations with Hayes via text messages on Monday, the center was staying positive.

“He said in one of the texts that he sent me, ‘A.V., we got this early, I would love to still be around the team during training camp to be able to go to the meetings. We’ve got a lot of new faces and I’d like to help out,'” Vigneault said. “I’m all for that, I told him I wouldn’t expect anything less from him, I want him around the team.”

Hayes is a critical part to this team. The 29-year-old second-line center is a member of the club’s leadership group and one of its toughest forwards to play against because of his size and reach. Over his two seasons with the Flyers, he leads the team in shorthanded goals (four), ranks third in shots (302), tied for fourth in goals (35), fifth in penalty kill minutes (211:01), and sixth in points (72).

Hayes’ absence on the ice opens the door for some of the Flyers’ younger centers to seize opportunity. Morgan Frost, a 22-year-old playing prospect, comes right to mind when dissecting the Flyers’ depth down the middle.

“He’s one of the young players who’s going to get an opportunity here,” Vigneault said.

“It’s an opportunity for some other players to step up and get that ice time that’s available right now.”

Claude Giroux and Scott Laughton give the Flyers some flexibility, as well, given they can play center or winger. The offseason acquisitions of Derick Brassard and Nate Thompson have become even more important.