Trailing by six with under three minutes to play, Irvine (11-5) got a bucket from Best to spark an 8-0 run capped by his winning jumper with 20 seconds left. New Mexico State's Ian Baker missed a 3-pointer at the buzzer.
Young was 7 of 14 from the field with five rebounds and three assists. Best finished with six points. The Anteaters hit 21 of 54 from the field (39 percent) and forced 16 turnovers while committing just seven.
New Mexico State (8-7) controlled the boards 35-30 but got to the line just once, hitting its only free throw attempt compared to Irvine's 8 for 13.