** ADVANCE FOR WEEKEND EDITIONS, OCT. 20-21 ** Workers prepare the arena and set up the boxing rings at the University of Illinois-Chicago Pavilion in Chicago, Wednesday, Oct. 17, 2007, for the upcoming 2007 AIBA World Boxing Championships. Nearly 700 amateur boxers from about 120 nations will be competing from Oct. 23 through Nov. 3, 2007, in this qualifier for the 2008 Beijing Olympics. The tournament is also Chicago's shot to prove the American bid city for the 2016 Summer Games can host an Olympic-style event. (AP Photo/M. Spencer Green)