TORONTO (AP) — Tampa Bay Lightning star defenseman Victor Hedman has been ruled out after appearing to twist his right ankle midway through the first period of an NHL playoff round-robin game against the Philadelphia Flyers on Saturday night.

Hedman went down untouched as he spun around to skate backward at the Tampa Bay blue line with the Flyers' Tyler Pitlick driving up the right wing. The NHL's 2017 Norris Trophy-winner got up slowly and broke his stick while heading down the tunnel to the locker room.

The Lightning did not provide any details in announcing on their Twitter account that Hedman would not return.

The Lightning did not have an update on Hedman, who is also a Norris Trophy finalist this year.

The Lightning and Flyers are closing their preliminary round-robin schedule with 2-0 records, with the winner clinching the Eastern Conference's top seed entering the first round of the playoffs, which opens Tuesday.

Tampa Bay is already missing captain Steven Stamkos, who has yet to play after sustaining a lower body injury before the start of training camp last month.

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