Ole Miss (7-2) snapped a two-game losing skid, coming back from a 56-50 deficit with less than eight minutes remaining. It was the most points for Summers since he scored 28 in a season-opening victory against Troy.
The Rebels took a 61-60 lead on Henderson's 3-pointer with 5:33 remaining and never trailed again. Henderson hit another big 3-pointer with 28.7 seconds remaining to give Ole Miss an insurmountable 69-63 lead.
Ole Miss broke a four-game losing streak in the series against the Blue Raiders.
Middle Tennessee has been a difficult matchup for the Rebels in recent years and Saturday's game was no exception. The Blue Raiders won 28 games last season and made their first trip to the NCAA tournament since 1989.
Ole Miss coach Andy Kennedy juggled the starting lineup after a two-game losing skid to Kansas State and Oregon. Henderson started his first game of the season after coming off the bench in the previous seven. LaDarius White also started for just the second time this year and added 11 points.
The changes didn't have an immediate impact, with the Blue Raiders jumping out to a 9-6 lead.
But the Rebels didn't trail for long and pushed ahead 30-19 on Henderson's 3-pointer with 4:01 remaining in the first half. Ole Miss took a 37-30 lead into halftime.
Henderson had eight points at halftime -- a fairly slow start considering his 39-point outburst against Oregon in his last game. But he also had four assists, including several nice passes as the Rebels pushed ahead.
Ole Miss built its lead to 40-30 by early in the second half before Middle Tennessee began a methodical comeback. The Blue Raiders took a 50-48 lead on Tweety Knight's layup with 10:28 left.
But the Rebels didn't panic, and Henderson's 3-pointer for the 61-60 lead sparked the offense. Summers scored on a layup on the next possession and the Blue Raiders couldn't respond until it was too late.
MTSU made just 11 of 21 free throws (52 percent) to hurt its chances at the upset. The Blue Raiders had a 48-27 rebounding advantage.
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