Bill Cowher has a new job -- backup dancer for America ... and the dude is loving EVERY SECOND of it!!!
TMZ Sports has footage of the Super Bowl-winning coach stealing the spotlight at the band's Pittsburgh show on Thursday ... joining the guys onstage and busting out some spectacular moves for their hit song, "A Horse with No Name."
There was clapping. There was bouncing. And, you better believe there was singing.
We're told Cowher is a huge fan of the band and watched most of the show from the crowd before getting introduced on stage.
Cowher's name has been swirling around coaching gigs ever since he won Super Bowl XL with the Steelers in 2006 ... but by lookin' at this vid, we take it dude's lovin' retirement way too much to make a comeback.