Indiana’s undefeated season hit a scary moment this Saturday. Senior linebacker Aiden Fisher went down with a left knee injury during the first quarter against UCLA at Memorial Stadium. Fisher, the heart and soul of the Hoosiers’ defense, twisted awkwardly while attempting a tackle and didn’t return to the game. The timing was particularly cruel. He’d just intercepted UCLA quarterback Nico Iamaleava on the second play from scrimmage and returned it 25 yards for a touchdown, marking his first career defensive score. 

But on the Bruins’ very next possession, Aiden Fisher went down and was immediately helped off the field, leaving the sideline with a black brace wrapped around his left knee and a white towel draped over his shoulder.​

The good news came during halftime when Indiana coach Curt Cignetti addressed the injury during his FOX interview. “We don’t really know,” Cignetti said. “He’s walking around fine. It’s more precautionary.” Michael Niziolek later reported that Cignetti mentioned Fisher would “go through all the tests, x-rays, and MRIs to make sure he’s fine.” Aiden Fisher spent the rest of the game on the sideline in full pads but without his helmet. This is generally a sign that a player won’t return. Though he was seen moving around without a limp and actively engaging with teammates and coaches throughout the contest. 

He was even the last player into the locker room at halftime, high-fiving each defensive teammate as they walked off the field. The fact that he wasn’t rushed to the medical tent and stayed engaged on the sideline suggests this might not be a long-term issue, but Indiana’s taking the smart approach by running every possible test.​

If Fisher misses any time, the Hoosiers have already shown they’ve got capable replacements ready to step up. After Fisher went down, Isaiah Jones took his place and performed just as remarkably as Aiden Fisher. And the defense didn’t miss a beat in the 56-6 blowout. Jones immediately forced a fumble after he took the field.

Redshirt junior Kaiden Turner also saw increased playing time, getting reps in those trio packages despite logging just 30 defensive snaps through the first seven games. The depth chart had Jones and Turner listed as backups behind Fisher and Hardy going into the season, and both have proven they can handle bigger roles if needed.​

However, Fisher is arguably the most important player on the entire roster. He serves as the quarterback of the defense with coach-to-player communication in his helmet. Fisher became the first Indiana linebacker to receive first-team All-America recognition when he got the honors from the Football Writers Association of America and Phil Steele in 2024. Last season, he racked up 118 tackles, and this year, he’d already accumulated 48 tackles, 6.5 tackles for loss, and 2.5 sacks through seven games before Saturday’s injury. His leadership on and off the field is irreplaceable. 

For now, Indiana’s just playing the waiting game while Fisher goes through the full battery of tests. The fact that Cignetti wasn’t overly concerned and described it as precautionary is encouraging, especially since Fisher was moving around freely on the sideline throughout the second half. The MRI results will tell the full story. But for a team that’s been nearly perfect all season, losing their All-American linebacker would be the first real adversity they’ve faced in 2025.​

Cignetti’s confidence in Jones 

While Fisher’s injury had Indiana fans holding their breath Saturday, Curt Cignetti’s confidence in Isaiah Jones as a replacement wasn’t just coach-speak. It’s backed by what Jones has been doing all season. When asked about the tackles for loss and sacks that have made Jones Indiana’s statistical leader in both categories, Cignetti didn’t hesitate: “Everything’s earned, not given. He’s earned everything he’s got. He’s a real smart player, just like Fisher is.”

Cignetti explained that Jones is essentially following the same developmental trajectory Fisher took, just a year behind: “Fisher was just a year ahead of him in his development because when Isaiah came here as a freshman, he was injured.” That injury as a freshman delayed Jones’ progression. But now that he’s healthy and in his redshirt junior season, the London, Ohio, native has become Indiana’s most disruptive defensive player with 11 tackles for loss and 4.5 sacks through seven games.

What makes Jones such a seamless replacement is his football IQ. “He knows the ins and outs of the defense just like Aiden does,” Cignetti said. And that mental grasp of the system is what allowed him to slide into Fisher’s starting spot without missing a beat against UCLA. The fact that Jones was already getting significant playing time in Indiana’s three-linebacker packages meant he wasn’t being thrown into the fire unprepared. Now, Jones might be getting an extended audition to prove he’s not just a capable backup but a legitimate star in his own right.​