Bruce Springsteen Joins Zach Bryan Onstage For 'Atlantic City' Show: Watch

Fans were excited about the surprise appearances, with one tweeting: “Hearing that Bruce Springsteen, The Lumineers and Shane Gillis took the stage for Zach Bryan's finale tonight in Philly and lightning could he had knocked me down while leaving in the parking lot. and that would be fine with me.”

Another added: “Witness Bruce Springsteen and Zach Bryan blast the Chicken Man in Philly tonight. Then we had an all-night revival with Zach, Bruce and The Lumineers — it was crystal clear.”

This isn't the only time The Boss joins Bryan for a surprise performance. She also joined the rocker on stage at Brooklyn's Barclays Center on March 27, where they performed two tracks, including the pair's collaboration “Sandpaper.”

Following the album's July 4 release, the country singer thanked Springsteen for the feature.

“Thank you for the day @springsteen. Thank you for your kind words. thanks for letting me take this picture,” Brian captioned a photo of Springsteen X (formerly Twitter). “Thank you for making my whole life a dream of a younger me. a reason to believe.”

Fans of Springsteen's “I'm on Fire” will instantly recognize the chugging beat on “Sandpaper,” which is identical to the feel of the 1984 hit.

Bryan has covered Springsteen's in the past He was born in the USA classic “I'm on Fire” on several occasions, live and in the studio.