Cory Monteith and Matthew Morrison

The show went on for Matthew Morrison on Sunday night following the death of his Glee co-star Cory Monteith the night before.

According to The New York Times, Morrison changed his opening number to an a capella version of "What I Did for Love," a song from the musical A Chorus Line that Glee's Rachel Berry (Lea Michele) performed in Season 2. Morrison expressed his condolences for Monteith, whom he called a brother, and acknowledged it was "awkward" to perform following the tragic loss. But, Morrison told the crowd, "You guys came to see a show, I came to perform a show, so that's what we'll do. And we'll do it in Cory's honor."

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Another one of Glee's other original stars, Naya Rivera, spoke out for the first time about Monteith's death on Monday. "The entire Glee family and I are deeply saddened by this tragedy," Rivera said in a statement. "Cory was and always will be a part of my own family and a good friend. He was a special part of this world and will forever be missed. My heart goes out to Cory's family and Lea and while we are grateful for everyone's well wishes, privacy during this time of grief is greatly appreciated."