Trailing 57-56, Brown hit a jump shot for a 58-57 lead. He made the game-winning shot with 56 seconds left. Isaac Johnson answered with a layup with 39 seconds remaining. The game ended on Ronshad Shabazz's missed 3-point attempt that would have won the game for the Mountaineers.
Brown, who drilled a 3-pointer at the buzzer to beat Little Rock 72-69 last Saturday, had 21 points, three assists and two steals. Mike Hughes added 12 points and Montae Glenn chipped in eight with eight rebounds for Georgia Southern (14-5, 5-1).
Appalachian State was up 25-21 at the break and led 46-34 with 12:28 remaining. The Eagles rallied to take a 52-51 lead after Quan Jackson's dunk with 5:57 left.
Shabazz had 17 points for the Mountaineers (8-11, 3-3).
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