The legendary country music singer and songwriter had to cut his Salt Lake City show short Sunday.
The 84-year-old said he had breathing issues and was taken to the hospital.
Nelson later tweeted an apology saying "the altitude got me and and I am feeling better now and headed for lower ground."
This is Willie I am sorry to have to cut the SLC show short tonight The altitude got to me I am feeling better now & headed for lower ground— Willie Nelson (@WillieNelson) August 14, 2017
Nelson has battled multiple health complaints in recent years and even cancelled a few shows back in January, but he has since returned to traveling on the road.
His latest album "God's Problem Child" was released in May and became his 17th chart-topper on Billboard top country album's chart.
Nelson is due to perform in Galveston and Sugar Land in November.
PHOTOS: The life and times of Willie Nelson
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