Montreal Canadiens forward Max Pacioretty underwent an emergency appendicectomy Saturday.
The 24-year-old will miss three-to-four weeks, according to a brief Canadiens statement.
Pacioretty has four assists and a team-high 10 shots on goal in three games this season.
The six-foot-two, 196 pound American was drafted 22nd overall by Montreal in 2007.
Pacioretty has 53 goals and 65 assists in 205 games with the Habs.