Bigsby was one of nine players who recorded a carry for the Tigers, who generated 285 of their 497 total yards on the ground. Jarquez Hunter scored three rushing touchdowns, while backup quarterback Robby Ashford generated 168 total yards as he split time with starter T.J. Finley.
''We ran the ball effectively,'' Auburn head coach Bryan Harsin said. ''We want to run the football. Overall, it all starts with running the ball. ... We wanted to do that tonight, and I'd say we did that pretty well.''
At the 1:33 mark of the third quarter, the game was delayed for an hour and 27 minutes due to lightning. Bigsby scored from 39 yards out on the first play after the delay.
Finley finished 9-for-14 passing for 112 yards, one touchdown and two interceptions. Ashford took over at quarterback midway through the third quarter after Finley's second interception.
''I just looked at it as I got an opportunity to play ball,'' Ashford said. ''And that's all I wanted and all I asked for. Whether I'm going off the bench or starting, I just want to play football. Whichever way I can help the team is what I'm going to do every day.''
Mercer (1-1) had only 101 yards of offense in the first half but found late success after the delay. Fred Payton finished 21 for 36 passing for 197 yards and two touchdowns, both of which went to Devron Harper.
''It's always a great opportunity to play a team like this,'' Mercer head coach Drew Cronic said. ''I wouldn't say I'm proud of the way we played. I thought we hurt ourselves a lot. But I like the way we finished each half. We showed some resiliency, but way too many self-inflicted mistakes.''
Mercer: The Bears were unable to keep it as close as their last trip to Auburn, a 24-10 loss in 2017, but they still had some positive moments on both sides of the ball. Mercer plays only FCS opponents for the rest of the season, so it can build on a solid two-game start.
Auburn: The Tigers already have an interesting quarterback situation brewing after Finley's two interceptions and Ashford's effective debut. Harsin said Finley ''is our starter,'' but added that Ashford is ''going to play.'' Auburn has another non-conference game next week in which it will be a clear favorite before hosting Penn State, so the quarterback usage will be monitored closely.
In his first career start, Auburn inside linebacker Cam Riley finished with 15 tackles. It was a major step up for the junior, who only recorded 14 tackles during the entire 2021 season.
''I wasn't expecting to end with 15,'' Riley said afterwards. ''I told (linebacker Owen Pappoe) 15, but in reality, I wasn't really expecting that I would end the night with 15 tackles. ... The goal for the season was to end with 50 tackles.
''So, of course, after tonight, 50 has expanded. It's going way higher than 50. I'm aiming for 100 now.''
Mercer: The Bears have an off week before hosting The Citadel on Sept. 17.
Auburn: The Tigers host San Jose State next Saturday night.
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