Eric Church fans already know to expect the unexpected at his Outsiders Revival Tour. Still, concertgoers were treated to a surprise during the Chief's three-night stop at Orange Beach, Ala.'s the Wharf Amphitheater.

Lainey Wilson and Jackson Dean were the two opening acts for those shows, and on Saturday night (Aug. 19) — the last of the three Orange Beach dates — Wilson joined Church onstage for a duet.

They dusted off an oldie-but-a-goodie from Church's catalog, "Over When It's Over." That song comes off of his 2011 album, Chief, but was never released as a single — and sandwiched in between career songs like "Creepin'," "Drink in My Hand" and "Springsteen," it's easy to see how it got overlooked.

But "Over When it's Over" is still a Church classic, and the singer hasn't performed it much in his live set since his longtime backing singer and duet partner Joanna Cotten left the band in favor of her own musical pursuits.

But in Alabama, with Wilson on hand, Church brought his groovy, shuffling heartbreaker to the stage, and the "Watermelon Moonshine" more than held her own, belting out a vocal solo during the bridge.

Church's Outsiders Revival Tour resumes on Thursday (Aug. 24) in Saratoga Springs, N.Y., and Wilson is joining him for that stop too, so fans just might be treated to an encore of the pair onstage together.

Church's headlining tour is currently scheduled to run through the end of September.

Top 50 Eric Church Songs: His Greatest Hits and Best Deep Cuts

Eric Church’s best song fall into rows. There’s the sullen heartbreakers and the grateful lovers. There are the snarling social statements and buoyant bops. OK, there are only a couple of buoyant bops on this list of Church's 50 greatest songs, but they exist. 

He's been known to sample R-Rated burners and sage truth-tellers — and then there are two songs about murder. So, Eric Church’s songs fall into rows, but there are a lot of rows in his 15-year catalog. 

His best song? Taste of Country asked fans, staff and the industry to weigh in and then looked at chart success, sales data pop culture importance to choose No. 1 from No. 50. Songs with strong lyrical content rank high. Songs with creative production rank high. Songs with both ended up in the Top 5. 

More From K96 FM