Tampa Bay Lightning right winger Ryan Callahan is out indefinitely after undergoing an emergency appendectomy Monday night.
The 30-year-old had abdominal pain late Monday afternoon before checking into Tampa General Hospital for surgery.
Team spokesman Bill Wickett said Callahan's return to the ice is "undetermined" at this time.
"I found out when it happened, I don't know, a little after dinner, I think," Lightning coach Jon Cooper said. "He had discomfort and we had to check him in, and just like that he's got to go under the knife. But he's good, he's feeling really good. It's not something that's uncommon to [have]. I think it's something that just because of the way medical practices are today, it's much easier to come back from than I think in the past. You've got to give a lot of credit to our docs and stuff, we got to it before anything really bad, the word 'ruptured,' could have happened."
Asked when Callahan will return, Cooper said, "Who knows? Stranger things could happen. How long's the game from now? He's a pretty tough kid."
The Lightning advanced to the Eastern Conference finals and eliminated the Montreal Canadiens in Tuesday night's 4-1 Game 6 win.
Callahan has no goals and three assists in 12 postseason games.
In his first full season with the Lightning after being traded by the New York Rangers in 2013-14, Callahan matched a career high with 54 points.
Information from ESPN.com's Pierre LeBrun and The Associated Press was used in this report.
