"He had been feeling bad the past couple of days," the band's manager, Ross Schilling, told The Associated Press on Thursday. "He had performances Tuesday and Wednesday and sucked it up last night as far as performing with some pain."

Van Zant is expected to need at least a week to recover, which has forced the band to cancel the following shows: May 19 in Mountain View, CA; May 20 in 29 Palms, CA; and May 21 in Henderson, NV. No make-up dates have been announced for the canceled shows.

The band, which was inducted March 13 into the Rock and Roll Hall of Fame, is currently in the middle of a long national tour. Starting June 25, the group will embark on a 14-city co-headlining tour with 3 Doors Down, which will run through the end of July.

Formed in 1973, Lynyrd Skynyrd rose to fame in the '70s thanks to a string of hits that included "Freebird" and "Sweet Home Alabama." Original lead singer Ronnie Van Zant, back-up singer Cassie Van Zant and guitarist Steve Gaines were killed in October of 1977 when a chartered plane carrying the group crashed in Mississippi. Original guitarist Allen Collins was paralyzed in a 1986 car accident that killed his girlfriend, and died of respiratory failure in 1990. Original bassist Leon Wilkeson, who reportedly suffered from chronic liver and lung disease, died in 2001.

Skynyrd's most recent studio set is 2003's "Vicious Cycle." The group followed that up with last year's "Lynyrd Skynyrd Lyve," a double album and companion DVD that features the group's 2003 performance at the Nashville-area's Amsouth Amphitheatre.