Daniel Alexander added a career-high 18 points, Blake Davis 11 and Akachi Okugo 10 for the Antelopes (6-8), who broke a five-game losing streak. Larson also grabbed 12 rebounds to notch his 11th double-double this season.
Shaquille Boga scored a career-high 25 points and Javorn Farrell also scored 25, tying his career high, to lead the Broncs (4-11), who have lost seven straight. Shaquille Hines added 12 points.
Trailing the entire second half, the Broncs pulled within 84-83 on a Farrell's three-point play with 51 seconds to go, but Garrison hit a 3-pointer with 18 seconds left and the Antelopes made four free throws in the final seconds.