Aaron Anderson had 20 points, and North Dakota scored the first 10 points of overtime Wednesday and beat Montana 88-81.
Troy Huff and Brandon Brekke added 15 points apiece for the Fighting Sioux (3-1), and Brekke had 11 rebounds.
Will Cherry led the Grizzlies (3-2) with 28 points, and Kareem Jamar had 24.
In its first visit to Grand Forks since 1963, Montana erased a 14-point second-half deficit, going up 61-58 with 5:32 left in regulation on a 3-pointer by Keron DeShields, who had 10 points.
The teams then traded baskets until a frenzied final sequence. Anderson hit a 3-pointer to put the Fighting Sioux up 70-69 with 19 seconds left, but Jamar's layup eight seconds later got the Grizzlies back on top.
Anderson was fouled with 2 seconds left and made one of two free throws to send the game to overtime, where North Dakota put the game away.
