Willie Nelson surprises a crowd of unsuspecting fans during this big-time birthday celebration

Videos by Rare

Videos by Rare

Fans got a big surprise when Willie Nelson showed up unannounced at Asleep at the Wheel frontman Ray Bensen’s early birthday bash on March 14.

The celebration, which took place in Austin, Texas behind advertising firm GSD&M, is part of a South By Southwest tradition held to raise money for Health Alliance for Austin Musicians (HAAM).

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In this clip, Willie, 83, is shown jamming out to “Whiskey River” alongside Ray and the Avett Brothers. According to Austin 360, the harmonica-infused track, which appears on the country legend’s 1973 “Shotgun Willie” album, was the first of many in the set list he played that night.

Willie also teamed up with the birthday boy on a cover of Townes Van Zandt’s “Pancho & Lefty,” which you can watch in the Instagram clip below.

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Despite previous concert cancellations due to health concerns, Willie continued to delight folks with songs including one off his upcoming LP, “God’s Problem Child,” called “Still Not Dead.” After running through a dozen or so songs, he concluded his performance with the iconic “On The Road Again.”

Aside from Willie and the Avett Brothers, other artists in attendance included Sunny Sweeney, Wade Bowen, Randy Rogers, Shelly King, Marcia Ball, Carolyn Wonderland and Charlie Sexton. Ray turned 66 on March 16.

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