Breida scored on a 64-yard touchdown run to close the first quarter, and scored again in the third quarter as Georgia Southern (2-2) took a 21-6 lead.
Kevin Ellison threw for 85 yards and was intercepted once, but added 96 yards on the ground including a 37-yard run that set up Breida's second touchdown. BJ Johnson caught five passes for 76 yards and was one of two Georgia Southern receivers with a catch.
Brandon Bridge was 13 of 34 and threw for 149 yards and a touchdown for South Alabama (1-2). Shavarez Smith had 69 yards receiving and had a 28-yard touchdown catch to lead the South Alabama receivers.