INDIANAPOLIS — The halftime environment was intense. Indiana trailed 21-0 to Louisville, and not much was going right for the Hoosiers.

“Man, (the locker room) was serious,” sixth-year IU linebacker Aaron Casey said. “We knew that we were beating ourselves more than they were beating us, so we decided we had to lock in and trust each other.”

In the first half of Indiana’s 21-14 loss, the Cardinals’ offense did whatever it wanted. Georgia State transfer Jamari Thrash got loose for two enormous receptions — one an 85-yard touchdown from Jack Plummer. Louisville followed the touchdown with a pair of long drives where it punished IU through the run game. The result was the three-touchdown lead at the intermission.

But Indiana did not back down despite the deficit. Head coach Tom Allen dialed up a surprise onside kick, a perfect bouncing ball that landed in the hands of safety Louis Moore — who’s not even on IU’s regular kickoff team.

The special teams play fueled Indiana’s defense. After the offense capitalized with a touchdown, the defense got itself together. IU put more pressure on Louisville’s backfield, which made the game look completely different in the second half.

“It was a combination of schematic adjustments as well as our guys wrapping better, running their feet through contacts,” Allen said after the game. “Aaron Casey is a huge part of that. He continues to play well.”

Casey was used as a blitzer out of the middle linebacker spot much more in the second half. That contributed to the Douglasville, Ga. native logging two sacks and a violent tackle for loss on a reverse.

Louisville gained 302 yards of total offense in the first half, averaging 9.4 yards per play. IU’s defense — which didn’t let Indiana State’s offense score last week and only allowed Ohio State 23 points in Week 1 — got shoved around.

But in the second half, Louisville only had 120 yards of offense with a 4.0-yard average. Better focus and communication sparked the turnaround.

“We all just decided to trust each other, play our gaps, play our responsibilities, and we were able to lock in,” Casey said.

Casey led IU with 10 total tackles on Saturday. He now leads all Hoosiers with 28 tackles through three games this season. His play energized an IU crowd that didn’t have much to cheer for in the first 30 minutes of the game in Lucas Oil Stadium.

After being stuffed on fourth-and-goal on the 1-yard line in the fourth quarter, Indiana still fell short by a touchdown. One has to wonder what Saturday’s game would’ve looked like without the defensive mishaps in the first half.

“We just can’t give up the big plays whether it’s in the run game or the throw game, especially in the pass game in the first half,” Allen said.

Indiana was expected to lose handily to Ohio State in Week 1. The Hoosiers were supposed to trounce Indiana State last week. Saturday’s game was the first of IU’s season that was up in the air, and the team couldn’t pull through.

The loss moves the Hoosiers to 1-2. IU will host Akron next Saturday in its final non-conference matchup of the regular season.

“I feel like we played well in the first half, it was just the busted plays that we had was detrimental,” Moore said. “Second half we didn’t bust no coverages, you see what happened.”

This appears to be Indiana’s most talented (and healthiest) team since going 6-2 in 2020. The question is whether or not the Hoosiers can turn the talent into wins against teams they are capable of beating.