On March 12, 2008, he was fired as GM of the Broncos after being with the organization for 16 years.
Sundquist became general manager of the Broncos 2002 after 10 years in a player personnel role for the team.
Denver reached the playoffs three times under Sundquist's watch, including an appearance in the AFC championship game against Pittsburgh following the 2005 season.
Sundquist supervised pro and college scouting, and was responsible for salary cap and contract analysis.
In his role as general manager, Sundquist helped Denver land free agents such as John Lynch, Daniel Graham and Travis Henry. He also made trades such as the one with the Washington Redskins to acquire Champ Bailey, and another to obtain Dre Bly from the Detroit Lions.