Thomas was 19-of-31 passing for 256 yards with an interception and added 52 yards rushing on six carries. Corey Sutton had 173 yards receiving and three touchdowns -- both career highs -- for Appalachian State (9-1, 5-1 Sun Belt Conference).
Destin Coates scored on a 67-yard run and, less than a minute later, Chris Bacon's 34-yard pick-6 gave Georgia State (6-4, 3-3) a 21-7 lead with 1:38 left in the first quarter but the Mountaineers scored the next 49 points.
Sutton answered with a 20-yard TD catch 89 seconds later, Thomas scored on a 3-yard run and Shaun Jolly returned an interception 30 yards for a touchdown to give Appalachian State its first lead before a 1-yard touchdown run by Evans made it 35-21 at halftime.
Raykwon Anderson scored on a 5-yard run to give the Mountaineers a 56-21 lead with 11 minutes left in the game.
Coates finished with 97 yards rushing for Georgia State.
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