Also in 1991, Mason played as a power forward for the Long Island Surf of the USBL. In his one season with the Surf, Mason was named to the All-USBL First Team, averaging more 27.8 points and 11.2 rebounds per game, and he set a league record with 28 rebounds in a game. Ed Krinsky, general manager of the Surf, said, "I really believed he could play in the N.B.A. He was a huge guy with backcourt skills". Later that year, Mason was already on the New York Knicks' summer league roster, with Pat Riley as coach. In the year 2000, in celebration of the USBL's 15th anniversary, USBL fans voted on the "All-15 Team," a collection of the best USBL players from 1985 to 2000, many of whom went on to become renowned NBA stars, with Mason included among the 15.