The Rebels (9-7, 1-2) went on a 7-0 run to break away after the game was tied with five minutes to go.
Storr and Dia both hit jumpers during the run and Augusto Cassia completed a three-point play off an alley-oop pass from Storr for a 69-62 lead with 3:02 left.
The Tigers (12-4, 2-1) were not done yet, however, as Jacob Crews and Trent Pierce both hit layups to cut the lead to 69-66 with 1:26 left.
Cassia came through with a huge tip-in shot with 34 seconds left to get the lead back out to 71-66.
Storr hit 8-of-16 shots from the field, including 4-of-6 from the 3-point line. He also had five rebounds.
Dia collected 11 rebounds for a double-double.
Mark Mitchell led the Tigers with 20 points, along with eight rebounds and seven assists.
Jayden Stone added 16 points, four rebounds and four assists.
The Tigers built a 10-point lead with 12:19 left in the first half, but the Rebels outscored them 25-14 the rest of the way to lead 37-36 at the break.
Missouri hit five 3-pointers to build its early lead,
Stone led the charge with three 3-pointers in the early going. Crews, Mitchell and Pierce each hit one.
The Rebels kept picking at the lead and when Storr hit a 3-pointer with 4:10 left, the Rebels completed the comeback with a 27-25 lead.
Shawn Phillips Jr. re-tied it for the Tigers with a dunk with 3:43 left.
Storr followed with his fourth 3-pointer of the half and the Rebels led 30-27 with 3:27 after a 15-3 run.
The Rebels would not trail again in the first half as Storr hit a 17-footer, Kezza Giffa hit two free throws and Dia nailed a 23-footer to give Ole Miss a 37-33 lead with 15 seconds left in the half.
Mitchell, however, drained a 3-pointer with one second left to cut the halftime lead to one.
Stone led the Tigers at halftime with 12 points and Storr had 18 at the break for the Rebels.
