Jonathon Williams had 20 points and nine rebounds to lead Wagner (2-3). Ian Hummer, who scored a career-high 28 in a 72-53 win over Lafayette on Saturday, had 11 points for Princeton (2-4).
Orlando Parker scored five points in overtime for the Seahawks.
After Williams tied the game at 40-40 on a layup, neither team scored in the last 2:17 of regulation.
Princeton started quickly, scoring the first nine points of the game, capped by Mack Darrow’s 3-pointer 5:39 into the first half. T.J. Bray’s layup made it 15-8 with 8:01 left, and Clay Wilson made a 3-point shot for a 22-12 advantage with 2:21 remaining. The Tigers led 23-14 at the break.