Doggett was 5 of 10 from the field and added nine rebounds while Celestin knocked down four 3-pointers en route to 6-of-9 shooting from the field.
Both teams battled through seven ties and eight lead changes in the first half before Southern (14-13, 10-4 Southwestern Athletic Conference) took a 41-37 lead behind a Doggett free throw with 14:35 left in the second half.
The Jaguars never looked back, leading by at least six points the rest of the way.
Southern shot 53.2 percent (25 of 47) from the field and connected on 16 of 22 free throws. The Jaguars took 19 free throws in the second half after taking just three in the first half.
Demarquelle Tabb led Alabama A&M (5-17, 3-10) with 12 points.
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