From Franco Corelli: Prince of Tenors:

The battle between tenor and conductor reached a climax when Cillario denied Franco his ovation at the end of “E lucevan le stelle.” An infuriated Corelli flipped his overlong thumb to his teeth in disgust and ran offstage. The audience was left stunned, the orchestra still playing the ascending scale leading to Tosca’s entrance, and Tosca herself bursting on stage to find it empty and the audience buzzing around in a mini uproar. Backstage, Chapin saw Corelli screaming at Charlie Riecker, teeth clenched, eyes bulging. There was no time for discussion. Chapin grabbed Corelli and pushed him back on the stage, where he resumed his role.

Ah! Franchigia a Floria Tosca