Malik Smith scored a season-high 19 points, while Andre Hollins added 18 points and 10 rebounds for Minnesota (10-2), which was playing its first game in 10 days after taking a break for finals week.
Alex Phillips, Devin Patterson and CJ Carter each scored 15 to lead the Mavericks (8-4).
Smith, a senior who transferred from Florida International when head coach Richard Pitino left FIU to take the Minnesota job last summer, scored all 10 points in a 10-4 spurt that pushed the Gophers to their biggest lead of the game, 71-60 with 11:27 to play.
But Nebraska-Omaha quickly responded, with Justin Simmons making a jump shot and two free throws and Matt Hagerbaum throwing down a dunk in traffic to buoy the Mavericks. Minnesota missed the front end of two one-and-one opportunities, and Patterson's runner made it an 8-0 run and a 71-68 Gophers lead. Smith then knocked down another 3-pointer, his fifth of the night, but Carter converted a three-point play at the other end to cut the Gophers' lead back to three.
That's when Mathieu took over. He scored nine of Minnesota's next 11 points and showed off the full range of his offensive game in the process. The 5-foot-9 junior-college transfer converted a drive to the basket, hit an outside jumper, got to the free throw line and hit one of two, and finished the streak with a floating, one-handed runner that put Minnesota on top 85-79.
The first half was a back-and-forth affair that featured eight lead changes and 15 3-pointers, including 10 in 16 attempts for the Mavericks' snipers. Phillips hit 4 of 5 from behind the arc, while Carter and Patterson each hit a pair of 3s. Meanwhile, senior guard Caleb Steffensmeier entered the game in the final 16 seconds of the first half and canned a buzzer-beater from the corner that tied the score at 44-all at the break.The Mavericks entered the game having won five straight, including an 82-80 victory at Nevada last Saturday in their most recent game. With single-digit losses at Iowa and UNLV to its credit this year, Nebraska-Omaha is showing progress in just its third season as a Division I program.