Murray was scheduled to start Game 1 but left after suffering a lower-body injury in warm-ups. Fleury came on and made 31 saves as the Penguins cruised to a 3-1 victory to take a 1-0 lead in the best-of-seven series.
Penguins coach Mike Sullivan offered no public update of Murray's status on Thursday, saying only there's no timetable for Murray's return.
Murray helped Pittsburgh to the franchise's fourth Stanley Cup as a rookie last spring and had taken over the No. 1 spot from Fleury this season.
Fleury's appearance on Friday will be his 102nd in the playoffs, a franchise record for a goaltender.
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