Willie Nelson played a surprise set during Ray Benson's birthday party, held during SXSW 2017, on Tuesday night (March 14).

According to Austin360, Nelson took the stage around 9:30PM, opening his set with "Whiskey River." He covered Townes Van Zandt's "Pancho & Lefty" with birthday boy Benson, played “Still Not Dead," a song from his forthcoming new album, God's Problem Child, and closed his show with "On the Road Again." Readers can press play above to see a snippet of the performance of "Pancho & Lefty;" below is a snippet of "Roll Me Up and Smoke Me When I Die."

Benson's birthday party concert is an annual SXSW tradition, to raise money for the Health Alliance for Austin Musicians (HAAM). Billboard reports that since 2005, the event has raised $4.9 million to help provide health care for more than 4,400 musicians; the goal for 2017 was to raise $66,000 -- appropriate, as Benson is celebrating his 66th birthday this year, on Thursday (March 16).

In addition to Nelson, Benson's birthday bash featured performances from the Avett Brothers, Randy Rogers, Sunny Sweeney, Wade Bowen and more. In 2016, George Strait made a surprise appearance during the event.

Nelson will release God's Problem Child at the end of April. It will be the singer’s first project of all-new songs since Band of Brothers was released in 2014 and, unsurprisingly, will feature a tribute to his late friend Merle Haggard. Although he canceled a handful of shows in February, due to illness, Nelson has been back on the road as of late.

Willie Nelson Through the Years

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