Earlier this week, Chris Robinson dropped in on Howlin’ Rain’s San Francisco gig for a surprise cover.

The Black Crowes/Chris Robinson Brotherhood frontman took on lead vocals for Mott The Hoople’s “Sucker,” with Howlin’ Rain providing support.

In the past, Robinson took Howlin’ Rain on tour with The Black Crowes as well as his Green Leaf Rustlers band.

Watch the musicians reunite onstage in San Francisco below: