Carrie Underwood joins Rolling Stones in Toronto

Mick Jagger performs with Carrie Underwood during the Rolling Stones concert in Toronto on May 25, 2013.

By Randy Lewis

May 27, 2013 12 AM PT

No, Mick Jagger isn’t pointing in the photo above at Carrie Underwood, who joined the Rolling Stones at their Toronto tour stop Saturday night, just to say, “Does this authorized souvenir T-shirt rock or what? And it’s a bargain at $40 at RollingStones.com!”

Actually, they were singing “It’s Only Rock & Roll” as Underwood joined the ever-expanding list of guests during the group’s current 50 and Counting tour.

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So far on the U.S. tour, “The World’s Greatest Rock and Roll Band” has enlisted assistance from a raft of pop, rock and country stars, including No Doubt’s Gwen Stefani, Keith Urban, Dave Grohl, John Fogerty and John Mayer.

Underwood couldn’t contain her excitement at adding her name to that list, and on Saturday noted to her Twitter followers: “8 years ago today, I won @AmericanIdol and tonight, I sang with the @RollingStones! Wow, so much has happened! #Thankful.”

The Stones, for their part, tweeted: “The Rolling Stones & @carrieunderwood! Check out Carrie’s T-shirt: #Stones50 #Toronto pic.twitter.com/ivFtZD5Bd2.”