 During his time in Stillwater, McArthur played on two Final Four teams, playing in the NCAA championship game in 1949 (a 46-36 loss to Kentucky) as a sophomore and the national semifinals as a senior in 1951.In that senior year of 1950–51, McArthur averaged 11.6 points per game and led the Aggies to a 29-6 record.The team won the Missouri Valley Conference for the second time in McArthur's career.