Red Hot Chili Peppers didn't play live at Super Bowl halftime

The Red Hot Chili Peppers are giving it away now -- acknowledging that they didn't play live instruments during their Super Bowl halftime performance.

The group's bassist, Flea, said in a letter to fans posted on the group's website Tuesday that the Rock and Roll Hall of Fame members pretended to play along to a pre-taped track of "Give It Away” during Sunday’s show. The request came from NFL officials who felt it was too difficult to pull off a completely live performance because of potential sound issues.

The admission came after observers noted Flea and his bandmates weren't plugged in while performing Sunday at MetLife Stadium in East Rutherford, N.J.

Flea wrote on the band's website that the opportunity was too big for the lifelong football fans to turn down. After internal debate, dubiously checking with fellow musicians and consulting with headliner Bruno Mars, they decided it was "a surreal-like, once in a life time crazy thing to do and we would just have fun and do it."

"I am grateful to the NFL for having us. And I am grateful to Bruno, who is a super talented young man for inviting us to be a part of his gig. I would do it all the same way again," he added. "We, as a band, aspire to grow as musicians and songwriters, and to continue to play our guts out live onstage for anyone who wants to get their brains blown out."

The 51-year-old said the group pre-recorded a unique instrumental track for the show. He didn't directly address whether Mars also recorded instrumental tracks for his appearance, though he said Mars was aware they did. A publicist for Mars did not immediately respond to an email requesting comment.

A record 115 million people tuned in to watch Mars and the Peppers, besting audiences of 114 million for Madonna and 110 million for Beyonce.