"The Who fans got an extra special treat tonight in Los Angeles," Live Nation wrote in an Instagram post, which was shared on Perry's account. "As The Joe Perry Project got the party started, Joe brought out Steven Tyler for a set that we'll be talking about for years!"
Perry and Tyler's onstage reunion happened on the same day Aerosmith announced a new collaborative EP with Yungblud, One More Time, which is due out Nov. 21. The EP's first single, "My Only Angel," will premiere on Friday.