Willie Nelson had Johnny Depp. And now Dickey Barrett has Jimmy Kimmel.

The trend of unlikely musical guests on Boston stages will continue tomorrow night as Barrett and the Mighty Mighty Bosstones will welcome the Jimmy Kimmel Live host to their outdoor show at City Hall Plaza. “Dicky Barrett’s Birthday Bash,” part of the Phantom Gourmet BBQ and Music Festival, also features New Jersey rock band the Gaslight Anthem and local soul veteran Barrence Whitfield & The Savages.

We’re told Kimmel is “an accomplished clarinet player” and will be joining the Bosstones on stage for a few songs tomorrow night. Kimmel and “Cousin Sal” from Jimmy Kimmel Live surprised Barrett in Boston this morning by rolling up unannounced. The trio know each other well: Barrett is Kimmel’s announcer on the ABC late night show.

Want to win tickets to Dicky Barrett’s Birthday Bash? Just email DICKIE in the subject line to michael@vanyaland.com and we’ll select a few winners at random by 3 p.m. EST this afternoon, good for a pair of tickets each.

You know you’ll want to be in the middle of Boston when the Bosstons play this classic…