McMillen led Maryland to a 73-17 record in the early 1970s. He averaged 21 points and 10 rebounds for his career. He was a first-team all-Atlantic Coast Conference player twice and was the most valuable player of the 1972 National Invitation Tournament championship game – a 100-69 victory over Niagara. McMillen, a 6' 11" power forward/center, was a member of the 1972 United States Olympic team that won a silver medal after a controversial finish in the gold-medal game against Russia. He went on to be a Rhodes Scholar and served as a U.S. Congressman from 1987-93.