TAMPA -- Pittsburgh Penguins defenseman Trevor Daley was seen leaving Amalie Arena on crutches Friday, the result of an injury sustained in the second period of a 4-3 loss to the Tampa Bay Lightning in Game 4 of the Eastern Conference Final.
Daley was checked into the end boards on a shoulder-to-shoulder hit by Lightning forward Ryan Callahan with 9:27 left in the period. It was unclear exactly how Daley was injured, but he went down in a heap, stayed down, tried to get up but couldn't, and shuffled on his knees to the front of the net as play continued around him until a whistle blew when Sidney Crosby touched the puck 20 seconds later.
Daley could not put any weight on his left leg as he was helped off the ice by Crosby and a trainer.
Daley was averaging 22:10 of ice time per game and had six points (one goal, five assists) in the Stanley Cup Playoffs heading into Game 4. He played 10:12 over 15 shifts before he was injured.
"He's a hard guy to replace," Penguins coach Mike Sullivan said. "He plays a lot of minutes. He plays in key situations. It's hard enough going down to five [defensemen], but when you lose someone like Trevor that plays important minutes for us, it just makes it that much tougher."
Video: PIT@TBL, Gm4: Daley leaves with injury in the 2nd
The Penguins might have to play without Daley going forward, into Game 5 at Consol Energy Center on Sunday (8 p.m. ET; NBCSN, CBC, TVA Sports) and potentially beyond in the best-of-7 series that is tied 2-2. He has many roles, including on the power play and penalty kill.
"It's big," said Pittsburgh defenseman Kris Letang, who played 31:38 in part because of Daley's absence. "He's a huge player for us. He plays a lot of minutes, got a lot of speed, plays power play, PK and he's a great leader in our room."
The Penguins at least have a natural replacement for Daley because of their depth on defense. Olli Maatta, typically a top-four defenseman when healthy, has been a healthy scratch for the past three games after being on the wrong side of a few plays in Game 1. He missed three games in the second round against the Washington Capitals with what was believed to be a head injury.
Derrick Pouliot is also an option for Sullivan, but it's hard to see him not using Maatta if Daley is unable to play.
"It's a huge spot to fill," Letang said, "but it's the playoffs and somebody has to rise to the occasion if he's not playing."