Johnson made three 3-pointers, and Gibson had a game-high six assists.
Two free throws by Ryan Whitehead with 8:13 to go in the first half broke a 26-26 tie and gave the Roadrunners (2-1) a lead they never relinquished. They led 39-32 at intermission and extended the gap to as many as 15 twice in the second half.
The Division II Aggies (2-0), for whom the game was an exhibition, played outscored UTSA from the floor 55-54 but suffered a huge disparity at the line. The Roadrunners sank 17 of 22 free throws to just 6 of 10 for Cameron.