In a statement, the team said Johansen needed emergency surgery Thursday night at Vanderbilt Medical Center. It did not specify when in Game 4 that Johansen was hurt.?
The 24-year-old is expected to recover in two to three months.?
Johansen is a finalist for the Selke award, given to the NHL's best defensive forward. He has enjoyed a big postseason, with a team-high 13 points (10 assists, three goals) in 14 games.
He's also been in the spotlight against the Ducks, getting visibly upset early in the series with Ducks center Ryan Kesler, telling media: "It just doesn't make sense how he plays the game. I'm just trying to go out there and play hockey, and it sucks when you've got to pull a stick out of your groin every shift. He doesn't do anything that makes sense. He thinks he's getting under guys' skin, but I don't know what he's doing."
Kesler later responded: "He's not my friend, he's not going to be my friend."
The Predators also could be without captain Mike Fisher, a depth-line center. Fisher was injured during the third period of Game 4 when Anaheim defenseman Josh Manson accidentally hit him in the head with a knee while leaping to reach a puck.
To address their sudden depth problems down the middle, the Predators could promote center Calle Jarnkrok to their top line while moving Colin Wilson from wing to center. They also could activate 37-year-old center Vernon Fiddler, who played in the first two games of the conference finals before sitting out the past two.
Johansen is the second key Nashville player to incur a season-ending injury in the playoffs. Young Swiss forward Kevin Fiala broke his leg in the opening game of the Predators' second-round series against St. Louis last month
Game 5 of the Western Conference finals series against the Ducks is Saturday in Nashville. The series is tied 2-2.?
Information from The Associated Press was used in this report.