Texas led by 33-30 at the break, but made 10 straight free throws to keep NMSU at bay late in the game.
Elijah Ingram led NMSU with 16 points, six rebounds and five assists. Hatila Passos had 15 points and eight rebounds, and Justin Hawkins had 11 points and three assists for the 13th-seeded Aggies (25-9), who made their first trip to the tournament since 1999.
They trailed by only 53-52 with 10:29 left, but could not gain the lead down the stretch.
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