See Willie Nelson, Avett Brothers Jam at Ray Benson Birthday Bash

"Whiskey River" performance took place at all-star event featuring Sunny Sweeney, Wade Bowen and Randy Rogers

Willie Nelson was a special guest at Asleep at the Wheel bandleader Ray Benson's Birthday Bash in Austin Tuesday night.

Asleep at the Wheel bandleader Ray Benson's annual birthday bash kept the special surprise guests coming until late in the evening Tuesday night, getting the legendary Willie Nelson on the road again after he was briefly sidelined by illness last month.

Staged in the backyard of advertising firm GSD&M, and coinciding with Austin's annual South by Southwest event, the all-star jam offered homegrown entertainment from the Lone Star State and beyond, with Benson joined by fellow Texans Sunny Sweeney, Wade Bowen and Randy Rogers, among several others. Austin360.com notes that Benson's 66th birthday celebration also included North Carolina's Avett Brothers joining Benson and his acclaimed Western swing band for a short Bob Wills-inspired set as well as the Avetts paying tribute to Merle Haggard with their version of "Mama Tried."

Striding onstage at 9:30 p.m. to the delight of the crowd, Nelson opened his set with "Whiskey River," teamed with Benson on the Townes van Zandt classic, "Pancho & Lefty," which Nelson famously recorded with Merle Haggard, and even offered a track from his upcoming God's Problem Child LP, the wryly observed "Still Not Dead." The 83-year-old closed with the ubiquitous "On the Road Again," which is fitting given the week he has planned. On Thursday, he's at his "Luck, Texas" ranch in Spicewood for the Luck Reunion concert featuring Margo Price, Brent Cobb and more. The following night, he's in Thackerville, Oklahoma, and on Saturday, March 18th is slated to play RodeoHouston.