Florida Panthers center Aleksander Barkov (16) hoists the Stanley Cup after winning Game 6 against the Edmonton Oilers.

The Florida Panthers' defense of their back-to-back Stanley Cup championships is facing a serious challenge even before the season opens Oct. 7.

Panthers captain Aleksander Barkov is having surgery on his right knee, coach Paul Maurice told reporters Friday. Barkov was injured during Thursday's practice and needed assistance standing up and getting off the ice.

The coach said he hoped to have a timeline later in the day.

"There's no hiding it," Maurice said. "That's the big man. He plays such an important part in the locker room. ... I know there's the idea: next man up. I get that, but there's not a next man for Barkie's skates."

Barkov has won the Selke Trophy three times as the NHL's top defensive forward, including the last two seasons. He has been captain since the 2018-19 season.

Friday's news means the Panthers will be without three forwards who helped them win the Stanley Cup last season.

Forwards Matthew Tkachuk and Tomas Nosek are out after offseason surgery, with Tkachuk expected back "December-ish" and Nosek expected to miss months.

Aleksander Barkov stats

Barkov, who centers the Panthers' top line, ranked second on the Panthers in the 2024-25 regular season with 71 points, despite missing 15 games. He had another 22 points in 23 games in the playoffs to help the Panthers win a second consecutive title.

Tkachuk had 23 points in the playoffs after returning from a 4 Nations Face-Off injury. Nosek played a key role in helping the Panthers overcome a 2-0 series deficit against the Toronto Maple Leafs when Maurice changed up his fourth line.

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This article originally appeared on USA TODAY: Aleksander Barkov knee surgery a setback for Panthers' Stanley Cup defense

Reporting by Mike Brehm, USA TODAY / USA TODAY

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