TORONTO - Canadian tenor Ben Heppner has withdrawn from the Canadian Opera Company's 60th anniversary concert due to a virus.

Heppner was to be one of the main draws of a show scheduled for Saturday at the Four Seasons Centre for the Performing Arts. He said in a statement he would not be capable of delivering a first-class performance after catching a viral infection while singing in "Tristan und Isolde" in London.

Still, the show will go on.

Tenor Ramon Vargas and baritone Russell Braun will sing at the concert, which will mark conductor Johannes Debus' debut as the COC's new music director.

The COC said in a release that additional performers would be announced this week.