Coach Mike Sullivan said DeSmith underwent core surgery on Friday morning and will miss the rest of the postseason.
The surgery comes three days after DeSmith exited in the second overtime of Pittsburgh's 4-3 triple-overtime victory over the New York Rangers in Game 1 of their first-round series. DeSmith entered the playoffs as Pittsburgh's top goaltender with All-Star Tristan Jarry sidelined with a lower-body injury.
DeSmith's injury leaves Louis Domingue as the starter as the best-of-seven series shifts to Pittsburgh for Game 3 on Saturday night.
Domingue picked up the victory in Game 1 when the Penguins won 5:58 into the third extra period. The well-traveled 30-year-old Domingue made 35 saves in a 5-2 loss in Game 2.
Sullivan hasn't ruled out Jarry's return at some point in the series. Jarry hasn't played since injuring his foot on April 15.
While Jarry has been rehabbing off the ice, there is no timetable on when he may be available, leaving Alex D'Orio as Pittsburgh's primary backup as the Penguins try to advance out of the first round for the first time since 2018.
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