Raijon Kelly added 15 points and seven assists, Brandon Hayman scored 14 and Tim Williams chipped in 13 to help Samford (7-12, 5-1) win its fourth straight game.
Ahead 59-58 with 10:54 left to play, Geffrard’s jumper sparked a 6-0 run, making it 65-58 with 6:14 remaining.
After Appalachian State got within two, 67-65 on Nathan Healy’s 3-pointer with 2:38 to go, the Mountaineers then turned the ball over twice, and missed five shots in the final 53 seconds to seal the victory for Samford.
The Bulldogs shot 54.5 percent (30 of 55) for the game and dominated inside, outscoring the Mountaineers 38-22 in the paint.
Jay Canty scored 19 points and grabbed eight boards for Appalachian State (7-10, 3-3).