Former Rangers fan favorite Ron Duguay — who played six seasons in New York and became a MSG Network analyst — made a one-night only appearance in the musical “Rock of Ages.”

But the show turned into a de facto Rangers pep rally the night before the team opened the Stanley Cup Final.

Retired Canadian pro Duguay played the role of “The Bourbon Room Bartender” in the hit show, and fans in the audience yelled out, “Go Rangers!” when he appeared onstage. Spies said the performance ended with the cast in Rangers gear, leading the crowd in a “Let’s go Rangers” chant.

Duguay told us of the experience, “How could you not have a blast? The guys are great and the women are beautiful.”

Bruce Glikas/FilmMagic