Prewitt was 9 of 15 from the floor and grabbed seven rebounds. Sean Sheldon added 14 points and Terry Tarpey chipped in 12 for William & Mary (2-0). David Cohn had seven assists and four steals with 4 points.
The Tribe, which never trailed, took a 42-30 halftime lead and won the second half 43-30. William & Mary scored 46 points in the paint while limiting WAU to 34. The Tribe also had 24 points off fast breaks and the Shock had 11.
William & Mary made 32 of 69 (46.4 percent) from the floor, while limiting the Shock to 22-of-63 (34.9 percent) shooting.
Brian Bridgeforth made 6 of 13 from the floor for 13 points to lead Washington Adventist.