In 1971, Swenson only placed third in the AAU outdoor meet (behind Juris Luzins and Jamaica's Byron Dyce); however, he won gold at the Pan American Games in Cali, running 1:48.08. At the 1972 Olympic Trials Swenson ran 1:45.1, his best time since 1970; he lost to Dave Wottle (who equaled the world record of 1:44.3) and Rick Wohlhuter, but took the third and final Olympic qualifying spot ahead of early leader Jim Ryun. At the Olympics in Munich Swenson qualified from his heat, but was disqualified in the semi-finals.
Swenson continued his career for several more years; in March 1975 he joined the International Track Association (ITA), a professional circuit. Swenson set his personal best for the mile run, 3:59.1, in an ITA meet on May 3, 1975; he was the 75th American to run a four-minute mile.
Notes
↑The previous record was Jim Ryun's 1:44.9 from 1966. Ryun's time had been set at 880 yards (804.672 m), and was worth about 1:44.3 for 800 m.
↑At the time, track and field was primarily an amateur sport, and most athletes only received under-the-table money. Professional athletes were not allowed to compete in the Olympics or other amateur meetings.