Smith missed 13 of 17 shots from field but made up for it shooting 12 of 15 from the foul line. Nigel Ribiero added 10 points for Grambling (11-12, 7-3 Southwestern Athletic).
With Grambling leading 69-66, Smith fouled Jared Sam with five seconds left after he converted a layup to reduce Southern's deficit to a point. But Sam missed the potential and-1 chance to tie it and time ran out.
Sam's layup gave Southern a 41-32 lead with 13:32 left. Grambling later went on an 8-0 run and Jackson tied it at 45 with a dunk. The teams traded leads before Jackson made two foul shots for a 61-60 lead that Grambling never gave up. Ribeiro made two fouls shots for a 69-66 lead with 15 second left.
Sam led Southern (9-14, 5-5) with 23 points on 7-of-10 shooting from the field and 9 of 11 from the free throw line and Aaron Ray scored 14.
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