Final chance for Heppner, Voigt

At this rate, Ben Heppner and Deborah Voigt may never sing “Tristan und Isolde” together.

After missing the first four performances of the highly anticipated revival at New York City’s Metropolitan Opera, Heppner planned to return Tuesday night.

But Voigt woke up Tuesday with a fever and nausea, spokesman Albert Imperato said. She was to be replaced by understudy Janice Baird.

Heppner and Voigt, two of the world’s leading Wagnerian singers, have never sung the opera together and have one more chance: Friday night.