In February 1997, D.C. United selected Presthus in the second round (20th overall) of the 1997 MLS College Draft. Presthus spent most of the 1997 as a backup to Scott Garlick. However, by the end of the 1998 season, Prestus had begun to emerge as United's top goalkeeper and the team traded Garlick during the off-season.
On February 5, 2001, United traded Presthus and a tenth round 2001 MLS SuperDraft pick to the Columbus Crew for third round pick in the 2001 MLS SuperDraft. Presthus became the Crew's starting goalkeeper, but on July 23, 2003, he tore the ulnar collateral ligament in his right elbow during a game. He underwent surgery on September 30, 2003, but the rehabilitation went much slower than he expected. As a result, he announced his retirement on January 14, 2004.[3]
After retiring from playing, Presthus became a financial planner with The Financial Solutions Network. He is now a vice president with American Electric Power.