The Toreros stopped the Eagles on downs near midfield with 1:17 to play but couldn't generate any offense before downing a punt on the Morehead State 4-yard line.
Carter Cravens completed three straight passes to get the Eagles to the 35 before Wallace picked him off on the San Diego 42 and made a 38-yard return.
Williams capped an 80-yard drive late in the first quarter with a 2-yard run. Quarterback Dom Nankil capped another 80-yard drive with a 6-yard run that had the Toreros (2-6, 2/3 Pioneer Football League) on top 14-3 midway through the third quarter.
Cravens scored on a 2-yard run and ran in the two-point conversion on the first play of the fourth quarter. The Eagles then punted twice, leading to a San Diego field goal, before giving up the ball on downs and the throwing the late interception.
Nankil was 11 of 19 for 199 yards passing with two interceptions.
Cravens was 22 of 47 for 208 yards passing but the Eagles (3-5, 2-3) only had 31 yards on the ground.
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