Nelson, 91, did not take the stage Friday night in Georgia for the first show of the Outlaw Music Festival Tour. He is a tour headliner.
His team released a statement on Instagram, saying in part:
"We regret to inform you that Willie Nelson is not feeling well and, per doctor's orders, has been advised to rest for the next four days. He is expected to make a quick recovery and join the Outlaw Music Festival Tour next week. In the meantime, Lukas Nelson and the Family Band, along with a few guests, will perform a special set to include Willie's classics and other songs."
The Outlaw Music Festival Tour has a stop in Charlotte on Saturday night and one in Raleigh on Sunday. The tour includes other legendary musicians, like Bob Dylan, Robert Plant and Alison Krauss.
Nelson is expected to rejoin them next week.
The Outlaw Music Festival Tour will wrap up on September 20 in Gilford, New Hampshire.