Kevin Hayes’ severe drop in production this season had more to do with an injury than anything else.

The Flyers center recently had surgery to repair a core muscle, also known as a sports hernia, and plans to start skating again in early July. He has already started working out.

This season, Hayes had 12 goals in 55 games; he collected 23 goals in 69 games in his first season with the Flyers.

On Wednesday, he acknowledged “it was tough to get going in games” because of his injury, which started to affect him midway through the season. He gutted it out but clearly wasn’t himself and didn’t have the acceleration he showed the previous year.

Hayes, 29, said trainers Jim McCrossin and Sal Raffa did a “great job making it feel good enough” to play.

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With Hayes’ production dipping and Nolan Patrick (four goals in 52 games; minus-30 rating) unable to make a smooth return from a migraine disorder that caused him to miss the 2019-20 season, the Flyers suffered down the middle, which was supposed to be a strong suit.

Hayes should be back to his old self next season, but Patrick remains a big question mark. Claude Giroux and Scott Laughton are natural centers, but both are more effective at left wing. That might leave an opening for center Morgan Frost to make the team, or it could cause general manager Chuck Fletcher to explore the free-agent center market.

Among the 30-year-old-and-under centers who are pending unrestricted free agents and had a salary-cap hit less than $4 million this season are Mikael Granlund (13 goals, 27 points in 51 games; $3.75 million); Alexander Wennberg (17 goals, 29 points in 56 games; $2.25 million); and Erik Haula (nine goals, 21 points in 51 games; $1.75 million), who once had 29 goals for Vegas and played for Fletcher when he was the GM in Minnesota.

Fletcher’s main goal this summer, of course, is finding a right-side defenseman to play alongside Ivan Provorov on the top pairing.

The best two right-handed defenseman on the market are Carolina’s Dougie Hamilton, a pending unrestricted free agent, and Columbus’ Seth Jones, who is available in a trade.

Hamilton, who turns 28 next week, would be a perfect fit with the Flyers, but he will probably re-sign with Carolina. Jones would be a great consolation prize, and he has said he will test the free-agent waters when his contract expires after next season. So what would he cost in a trade? Plenty. And before the Flyers put together a hefty package, they would need to get assurances that Jones would sign a long-term deal here.

Would a package of, say, a first-round pick, Phil Myers, Patrick, and Laughton get it done?

Jones, who will turn 27 on Oct. 3 and has a modified no-trade clause, is a three-time All-Star selection and is in his prime. His defensive analytics slipped this season, but he played for a bad Columbus team.

The 6-foot-4, 209-pound Jones plays in all situations and averages about 25 minutes a game. He and Provorov would give the Flyers one of the league’s best pairings.

Jones’ father, Popeye, is a former NBA player who is now an assistant with the Sixers. Seth Jones’ brother, Caleb, 24, is an Edmonton Oilers defenseman.

Breakaways

Center Ross Colton, the pride of Robbinsville in Central New Jersey, scored a key goal Tuesday as Tampa Bay beat Carolina, 2-0, and won its second-round playoff series in five games. Colton, 24, a rookie who had nine goals in 30 regular-season games, was a former University of Vermont standout and a fourth-round selection (118th overall) in the 2016 draft. He was chosen nine picks after the Flyers took Connor Bunnaman, who has one goal in 39 NHL games. ... Hayes had four shorthanded goals in 2019-20 and none this season.