Haggard's publicist, Tresa Redburn, confirmed that Haggard was canceling 10 tour dates in September because of a chest infection. The 73-year-old singer-songwriter survived lung cancer in 2008.
Earlier this month, the Kennedy Center in Washington announced that Haggard would receive a Kennedy Center Honor along with composer and lyricist Jerry Herman; dancer, choreographer and director Bill T. Jones; songwriter and musician Paul McCartney.
The careers of those figures will be celebrated on Dec. 5, 2010. The gala ceremony will be broadcast by CBS on Dec. 28, 2010.