Willie Nelson has been forced to postpone two concerts over the last several days, citing an undisclosed illness.

The 83-year-old country music legend still keeps up a very active schedule of live appearances, regularly performing all over the country with his longtime band members, the Family. But he was forced to put off a scheduled show at the Wagner Noel Performing Arts Center in Midland, Texas on Sunday (Nov. 13).

CBS 7 News reports that the veteran entertainer had to postpone the performance because he was feeling "under the weather." The venue does plan to reschedule the date, and tickets for the postponed show will be honored at the rescheduled show.

Nelson also postponed a concert that was set for Tuesday night (Nov. 15) at the City Bank Auditorium in Lubbock, Texas. According to Everything Lubbock, a representative from Select-a-Seat made the announcement Tuesday morning. No information is available about a possible rescheduled date.

Nelson is almost always on tour, and most recently he's been out promoting a project that is very special to him. He released his most recent album, For the Good Times: A Tribute to Ray Price, in September, and recently performed "Heartaches By the Number" on Jimmy Kimmel Live!

“Ray was as a close a friend as you could have,” Nelson says in a video from Rolling Stone Country. “We traveled together, lived together, played music together, partied together ... and had a lot of good times.”

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