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.
Kelly, balanced Oregon St. beat UCLA 79-66
Kylor Kelley was a perfect six for six from the field and had 14 points and five blocks as Oregon State defeated UCLA 79-66 on Sunday night.
Michigan (17-0) off to best start in program history after drubbing Northwestern
No. 2 Michigan (17-0) set a school record for the best start to a season and tied the longest winning streak in program history after an 80-60 victory over Northwestern on Sunday night.
King, White help Oregon snap skid, beat USC 81-60
Paul White and Louis King each scored 19 points as Oregon raced past Southern California 81-60 on Sunday night.