A message posted on Haggard's official Web site said the 67-year-old singer-songwriter had canceled all shows for the rest of 2004 "due to health concerns."
At first, the posting prompted concern that Haggard's illness might be serious, but his publicist told United Press International Haggard only had a short series of dates scheduled from Oct. 1-10 and he was "just not in top-notch shape to sing" on those dates. No other dates had even been scheduled for the remainder of 2004.
The publicist said there was no information yet on whether Haggard would reschedule the October dates.
The singer of such country classics as "Today I Started Loving You Again," "Mama Tried" and "Workin' Man Blues" recently recorded two songs with country star Toby Keith in Los Angeles.
Haggard and Keith recorded "White Boys" for inclusion on an upcoming Haggard album, and "She's Not Hooked on Me No More" for Keith's upcoming project.