Ambrose Mosley tallied 16 points and grabbed six rebounds for Old Dominion (17-17), which will advance to the second round of the tournament to face the winner of Radford and Oregon State. Richard Ross scored 12 points, and Aaron Bacote chipped in 10 with five rebounds and five assists in the victory.
Jordan Dykstra scored 16 points to pace South Dakota State (19-13), as the forward connected on 4-of-9 from distance. Zach Horstman contributed 15 points for the Jackrabbits, and Cody Larson notched a double-double with 14 points and 12 rebounds.
Old Dominion was on fire to start the game, hitting 59.4 percent of its shot attempts, including 7-of-14 from 3-point range. The Monarchs went into the half with a sizeable lead, 48-33, after South Dakota State connected on 44.4 percent of its shots from the floor.
The Monarchs slowed considerably in the second frame, making just 24 percent of their field goal tries, including 1-of-7 from beyond the arc. The Jackrabbits couldn't take advantage of ODU's poor offense, as they shot just 38.7 percent from the field. SDSU was able to shave eight points off the Monarchs' first-half advantage, but still fell short.
Old Dominion outscored South Dakota State from the free-throw line, 14-8, and had an impressive 22-0 edge in points off turnovers. The Jackrabbits won the battle in rebounding, 41-32, and in second chance points, 20-9.