LSU (7-0) is off to its best start in five seasons -- when it won its first eight games.
Thornton, who played just 20 minutes, also tied his career-high with five assists and made 6 of his 9 field goal attempts.
Martin, who played only 17 minutes, came off the bench and shot 6-for-7 from the field, making a season-best four 3-pointers.
Ibrahim Kpaka led Grambling (2-6) with 14 points. Jarred Riley contributed 10 points. Andrew Prestley, Grambling's top scorer this season, scored seven points -- nearly six less than his per-game average.
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The dust has settled after players made their NBA draft decisions. Which college teams won? Which lost? Well, Villanova is pretty happy. USC, meanwhile, might not be as thrilled.
The 2017 recruiting class is short on point guards, with Trevon Duval leading only eight prospects from the ESPN 60 who are still available.
ESPN college basketball reporter Andy Katz looks into the two decommitments from the NBA draft and what they're looking forward to.