The All-Star scored his team-leading 20th goal in Monday’s 5-2 victory over Ottawa but was tripped up and crashed into the boards.
He appeared to avoid hitting his head full force, but rolled on the ice before getting up and skating off while favoring his right arm/shoulder.
Guentzel immediately went to the dressing room after getting his 200th career point.
General manager Jim Rutherford said in a statement that Guentzel had surgery at UPMC Presbyterian Hospital in Pittsburgh by team physician Dr. Dharmesh Vyas and orthopedic trauma specialist Dr. Ivan Tarkin.
“It was really scary,” coach Mike Sullivan said Monday. “Those are always dangerous when you fall that distance from the boards. There’s no status on him right now.”
Guentzel, 25, had a goal and an assist in the game and leads Pittsburgh with 43 points. He was named as the Penguins’ lone All-Star earlier Monday. He has helped the Penguins remain in the thick of the playoff chase with star Sidney Crosby on injured reserve due to surgery on a sports hernia.
Information from The Associated Press was used in this report.