In 1978, he was used mainly as a pass-rush specialist at left defensive tackle in place of Jethro Pugh or Larry Cole and emerged as a key reserve, registering 4 unofficial sacks (fourth on the team).
The next year, he had a contract holdout during training camp and asked for the Buccaneers to trade him to the Denver Broncos, in order to pursue his veterinarian interests in the offseason.
[10] On November 10, 1983, needing help on the defensive line, the Los Angeles Raiders signed Stalls to a short-term contract after the Denver Gold agreed to loan him.
[11] Although he didn't have the size, he was used as a pass-rushing nose tackle where his quickness created mismatches en route to the Raiders winning Super Bowl XVIII.
[13] After sitting out the previous year attending veterinary school at Colorado State University, he was signed by the Los Angeles Raiders as a free agent on July 21, 1985.
[15] After football, he experienced many careers such as marine biology at California State University, veterinary medical studies at Colorado State University, investment banking at Boettcher & Company and Stern Brothers, sales at MCI Telecommunications, youth advocacy with the Center for the New West, senior management with the City of Denver's Recreation Department, founder & executive director of The Spot (gang youth center), executive director of Aspen Youth Experience, President/CEO of Big Brothers Big Sisters of Colorado, and currently the founder & executive director of the Street Fraternity in Denver, Colorado.