Williams' 25 points and 13 rebounds were game-highs for Murray State.
The Racers set the tone early, starting with six defensive stops while building a 9-0 lead. The bolt from the starting gate opened with a layup by Jonathan Fairell and a 3-pointer from Fields. Fairell finished with 12 points and 11 rebounds. Cameron Payne had two steals in the run, dishing once to Fields on a fast break and scoring himself with a jumper.
The Racers (2-2) never trailed while shooting 50 percent from the field. They had a 44-29 rebounding edge and outscored the Wildcats 46-24 in the paint.
Walt Andrews scored 14 points and Gary Pollard 10 for Bethel (4-3).