In 1993, Gannon began broadcasting for ESPN and ABC (which was ), covering play-by-play coverage for college basketball and football; by 2001, he had covered three post-season bowl games. He was an announcer on ABC's coverage of the PGA Tour and the Champions Tour. He announced the Tour de France, which Jacobs called "perhaps his greatest challenge", three times. In 2001, ABC reported that Gannon hosted the Belmont Stakes once, and three times called the play-by-play at the Little League World Series. By the time he left ABC, Gannon had also covered the NBA, WNBA, horse racing, tennis, beach volleyball, skiing, supercross motorcycle racing, mountain biking, and golf. He announced for the 2002 FIFA World Cup, the 2003 FIFA Women's World Cup, WTA professional tennis, the 2004 Indianapolis 500, 2006 Belmont Stakes, the Special Olympics, the Goodwill Games, and hosted ABC’s college football studio show. For six years, he hosted the Tournament of Roses Parade.