In 1979, the fledgling ESPN cable sports network brought Simpson on board to provide some needed credibility with sports fans. Simpson broadcast the first NCAA basketball game the network televised, with flamboyant Dick Vitale as the color man. Vitale credits Simpson with helping him develop as a sportscaster. Simpson also called USFL and College World Series games for ESPN, and in 1988 called the Baltimore Orioles' local telecasts on WMAR-TV.
After his sportscasting days Simpson retired to St. Croix, Virgin Islands. Among other firsts he was the initial U.S. sportscaster to appear live via satellite from Asia, and he was involved in the first American sportscast using instant replay technology. In 2005, ESPN brought Simpson back from retirement to do play-by-play for a series of college basketball games in a "turn back the clock" format on the ESPN Classic network.
After week 2 of the 1979 NFL season, Simpson moved from NBC Sports to ESPN where he called games for college football, college basketball, college baseball, the USFL, and the NBA.