Vince Gill, Sheryl Crow and Willie Nelson are among more than a dozen major acts performing Saturday (July 28) at Eric Clapton's Crossroads Guitar Festival in Chicago. Taking time off the road, Nelson rescheduled a series of July tour dates, but a spokesperson confirms that he and his longtime harmonica player, Mickey Raphael, will be performing at the charity event. Hosted by comic-actor Bill Murray, the event at Toyota Park will also feature Alison Krauss & Union Station and Jerry Douglas. The festival raises money for Crossroads Centre, a substance abuse treatment center Clapton founded on the Caribbean island of Antigua. Others performing Saturday include Jeff Beck, Robert Cray, Buddy Guy, B.B. King, Sonny Landreth, Albert Lee, John Mayer, John McLaughlin, Robbie Robertson, Hubert Sumlin, Johnny Winter and Steve Winwood.