In recent days, Billy Joel has really been leaning into his status as a rock ‘n’ roll elder, especially in his regular gigs at Madison Square Garden, effectively his second home. Just in the past few months, Joel spearheaded the campaign to induct Warren Zevon into the Rock And Roll Hall Of Fame, and he covered Zevon at MSG. He’s also paid tribute to his generational peer Jeff Beck with a pair of covers. In LA a couple of weeks ago, Joel performed with Stevie Nicks. And last night, Billy Joel invited ZZ Top legend Billy Gibbons to his stage.

Billy Gibbons just played with Elvis Costello in Nashville a few weeks ago. Last night, he was Billy Joel’s surprise guest at Madison Square Garden. (In the fan-made video below, we get to hear someone yell, “Holy shit, it’s Billy Gibbons!”) The two Billys, along with Billy Joel’s backing band, ran through two ZZ Top classics, “La Grange” and “Tush.”

On “La Grange,” Billy Gibbons and Billy Joel traded off guitar and piano solos. During a break in the song, Joel casually raised a coffee cup in salute and called Gibbons “one of the good ones.” After the two songs were done, Joel called it “a fantasy come true.” The whole thing is fun to watch, and you can watch it below.