The original AmericanIdol champ joins Groban for a goose-bump-inducing performance of "All I Ask of You" from Phantom of the Opera. The song is featured on Groban's album Stages, which debuted at No. 2 on the Billboard 200 in May.
"When I was making this record, and we were going to record this song, I knew this duet had to be recorded in a very, very special way and it had to be recorded with a very special singer," Groban said of Clarkson. "She is one of the most versatile singers that I've ever heard."
Stages is a a collection of songs from Broadway musicals.
See more from Kelly Clarkson in the gallery below!