Jay Howard's rebound and put-back opened up the scoring in the game for LMS, but Whitthorne's Sanchez Borkeen tied it up.
Back-to-back buckets by Darius McKenzie and D'Andre Brown gave LMS a 6-2 lead before the Maury County middle school went on a 7-1 tear at the end of the quarter to take a one-point lead after the first six minutes.
Whitthorne's lead stayed at one-point at 12-11 before LMS exploded, ripping off 13 unanswered points, thanks to a suffocating defense effort from the hometown Tigers.
Howard put in a basket in the game-deciding spurt and McKenzie scored four points
Malek Sain also scored four markers during the run, including a trey and Brown nailed a three-pointer as the Tigers would go on to open up a huge 27-15 lead at the half.
A Howard rebound and put-back stretched the LMS lead to 14 points at 29-15 before Whitthorne made a run of their own, outscoring the home-towners 15-6 the rest of the third period to cut the LMS margin to three points at 33-30 on a Borkeen bucket with under 20 seconds remaining in the period.
Brown set things back right for Lewisburg, nailing a three-bomb at the buzzer to extend the LMS lead to a half dozen points, entering the final six minutes of hardwood action.
Sain drilled a trey on LMS's first possession in the fourth quarter, and after a Whitthorne miss, McKenzie scored on a traditional three-point play in the paint to open up a 42-30 margin.
LMS began to put on the defense and a Brown bucket off a Whitthorne turnover gave Lewisburg a 46-31 lead with three minutes remaining in the contest.
Whitthorne would get to within 12 points late on a Tristan Williams basket, before back-to-back baskets by Sain and Brown put the Maury County squad away.
Sain led the Tigers in scoring with 17 points, McKenzie was next with 14, Brown netted a dozen, and Howard finished with 9 points in the contest.