Dierdorf, a native of Canton, Ohio, attended the University of Michigan where he was a two-time all-Big Ten tackle and named to seven different All-America teams as a senior.

During his stellar career with the St. Louis Cardinals from 1971 to 1983, Dierdorf was named all-pro six times, was selected as the NFL's top offensive lineman three times and was voted to the NFL Team of the Decade for the 1970's.

Dan's broadcasting career began at KMOX radio, where he served in a variety of capacities, including host of the nationally-acclaimed "Sports Open Line" program, St. Louis Blues hockey coverage and St. Louis Cardinals football broadcasts. Dan also served as sports director for KMOV-TV. Dierdorf joined CBS Sports as a play-by-play announcer for the NFL telecasts in 1985 before switching to color analysis in 1986. In 1987, Dierdorf joined ABC Sports as an analyst of field events during the network's exclusive coverage of the United States Olympic Trials, and worked the 1988 Winter Olympic Games in Calgary.