It's hard to upstage Robert Plant as a concert guest, but Brian Johnson managed to do that on Sunday (May 14) in Oxford, England, when he and Plant both joined Bad Company's Paul Rodgers for a rendition of Barrett Strong's Motown hit "Money."

Paul Rodgers, Robert Plant & Brian Johnson at Oxford New Theatre 14/5/17

Uploaded by Sean Bateman on 2017-05-14.

The show was part of Rodgers' Free Spirit tour in the U.K., focusing on his work with his pre-Bad Company band Free. Johnson public appearances, especially singing, have been limited since he was removed from AC/DC last March due to hearing issues that he's been dealing with ever since; Guns N' Roses frontman Axl Rose stepped in to replace Johnson during AC/DC tours of Europe and North America.

On Sunday Johnson and Plant traded verses with Rodgers throughout the song, with Plant adding a harmonica solo. Rodgers posted a photo of his "Surprise guests in Oxford" on his Facebook page.

Surprise guests in Oxford...Brian Johnson and ...

Surprise guests in Oxford...Brian Johnson and Robert Plant

Robert, Brian and I contemplating life. I am ...

Robert, Brian and I contemplating life. I am still super charged from last night thanks guys. - Paul

Plant recently filmed a segment of Johnson's new television series "A Life On The Road” that will be airing later this year. He's been working with the maker of in-ear monitors on a new device that might allow him to fully return to the stage.

Gary Graff is an award-winning music journalist who not only covers music but has written books on Bob Seger, Neil Young and Bruce Springsteen.