Jackson attended the University of Louisville, where he was coached by current college football analyst Lee Corso. During his college career, he was a two-time Missouri Valley Conference player of the year selection.

Jackson was selected by the Denver Broncos in the 1973 NFL Draft. He enjoyed a 14-year career in Denver where he was a three-time Pro Bowl selection, a two-time All-Pro selection, and was voted Denver's Most Inspirational Player six times by his teammates. Jackson ranks second only to John Elway on the team's all-time list of games played with 191.

In 1987, Jackson joined ESPN where he was teamed with Chris Berman on the network's signature NFL shows, NFL Countdown and Primetime. On Monday Night Countdown, Jackson hosted the popular segment "Jacked Up!," which featured the five biggest hits from the previous day's games.

In 1992, Jackson was inducted in the Broncos' Ring of Fame. Jackson resides in Cincinnati, Ohio with his family.