After Western Kentucky generated 290 yards and 17 points in the first half, Auburn's defense held the pass-happy Hilltoppers to 105 yards and allowed zero points after halftime.
"That was special," Auburn defensive tackle Colby Wooden said. "That's one way to go out in Jordan-Hare (Stadium) - to hold them to no points in the second half. That's crazy."
Bigsby and Hunter both scored long rushing touchdowns, and D.J. James returned an interception 25 yards to cap 24 unanswered points for the Tigers in the second half.
Auburn (5-6, 2-5 Southeastern Conference) has won back-to-back games under interim coach Carnell Williams as it heads into its annual Iron Bowl matchup with rival Alabama.
"They had every reason to fold, every excuse," Williams said of his team. "They've been through a tough time. But, man, they want more. They have given me so much confidence to do this job."
Western Kentucky (7-5, 5-2 Conference USA), which has won four games against SEC opponents since 2012, was unable to carry a strong second quarter of offense into the second half.
Hilltoppers quarterback Austin Reed had 290 passing yards, two touchdowns and two interceptions in the loss. Malachi Corley had 99 yards on 12 receptions, while Joshua Simon caught both of Reed's touchdown passes.
"There were a lot of good things out there, but we stalled out and had a lot of third-and-longs," Western Kentucky coach Tyson Helton said. "And (Auburn) just played really good defense."
Western Kentucky: The Hilltoppers, who had already clinched bowl eligibility for the fourth straight season under Helton, showed how their fast-paced offense can be tough to handle. Western Kentucky will undoubtedly look back at its failure to finish several early drives, as it played Auburn evenly until the fourth quarter.
Auburn: The Tigers struggled in second halves earlier this season under Bryan Harsin, but they have now played well after halftime in all three games under Williams. While Auburn has had little to play for recently - except for an outside shot at making a bowl game - the team's energy has been noticeably different since the coaching change.
A BLAST FROM THE PAST
Hunter's first touchdown of the game was a passing one instead of a rushing one. Midway through the second quarter, Auburn called the same trick play - a halfback toss pass to the right side of the field - that Williams ran as a player for a touchdown pass in a 2004 win over Georgia.
"We threw some old 2004 Auburn plays in there," Williams said. "I told Jarquez, 'Hey, that halfback pass, it's gonna be a touchdown, now.'"
After struggling to establish a consistent rushing attack in the first half, Auburn averaged 7.9 yards per carry after halftime.
"We hit them in the mouth," Hunter said. "In the second half, we tried to go out there and dominate them."
Auburn has now recorded more than 250 rushing yards in all three games under Williams. It's the first time the Tigers have hit that mark in three straight games since the 2016 season.
Western Kentucky travels to Florida Atlantic on Saturday.
Auburn visits No. 8 Alabama on Saturday.