Rookie Dillon Thieneman Learning On The Fly For A Bears Defense Trying To Match Pace With Ben Johnson's Potent Attack

LAKE FOREST, Ill. — Caleb Williams seemingly placed the ball where only wide receiver Kalif Raymond could get it Tuesday during Chicago Bears training camp. Williams, the face of the franchise and this year's Madden 27 video game, slung a sublime pass that landed downfield in Raymond's bucket near the boundary.

To just about everybody watching outside Halas Hall, that completion marked one of Williams' top throws of the day. To rookie safety Dillon Thieneman, the play was the reason he voluntarily spent time after practice working on Cover 2.

"I could have probably got a little more depth, had a little more vision to Caleb to see where his eyes were looking so I could move that way," Thieneman told Yahoo Sports.

He explained that, as the offense's condensed formation expanded, he needed to get deeper and then take a better angle toward the ball.

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Thieneman, a do-it-all defensive back the Bears selected with the No. 25 overall pick in this year's draft, slapped his hands together in frustration once Raymond made the grab, with the 22-year-old close behind.

His defensive coordinator at Oregon, Chris Hampton, describes Thieneman as "routine-oriented." Ducks director of speed and performance Kyle Bolton said they used to call Thieneman "The Terminator."

"That dude, he's like a robot," Bolton remarked to Yahoo Sports.

Thieneman would arrive early, always sit in the same spot, have breakfast, stretch and then get a couple sprints in before the session began, even if it was a walkthrough. And he would always stay late, Bolton explained. 

That part of Thieneman's routine hasn't changed. He's carried it to the NFL, where he's committed to executing pre-planned drills or addressing a pain point from that day's practice so that he can visualize the moment bothering him and go through it again.

"Nobody has worked harder," Purdue defensive coordinator Kevin Kane told Yahoo Sports.

Kane, Thieneman's DC the first two years of his college career, added: "Nobody's put himself in a position to be where they're at today more than him."

Where Thieneman is today is on the starting defense of a Bears team that culture-changing head coach Ben Johnson wants to not only win the Super Bowl but also score the most points per game in league history. Thieneman is in the back end of a unit challenged with keeping pace.

He's among the fastest players on the team. He needs to be one of the fastest learners, too. 

The Bears are counting on him in a new-look secondary that has already lost reigning Super Bowl champion safety Coby Bryant for four to six months because of a left knee injury the former Seattle Seahawks standout suffered in camp.

How change of direction vaulted him to Chicago

Thieneman's stint at Purdue is well-documented. A three-star prospect from Westfield, Indiana, Thieneman followed in the footsteps of his two older brothers, Jake and Brennan, who joined the team as walk-ons and wound up playing roles in the Boilermakers' secondary.

Jake and Brennan, eight-plus and six-plus years Dillon's senior, mentored Dillon as he grew into a more heralded high school recruit than either of them. As the story goes, Dillon sports a No. 31 jersey because he's a combination of Jake and Brennan, and they wore No. 41 and No. 38 at Purdue (Dillon merged Brennan's "3" with Jake's "1" to make "31").

Jake and Brennan showed middle school Dillon what it meant to study and train like a college athlete. By the time Dillon reached West Lafayette in the winter of 2023 as an early enrollee on scholarship, he hit the ground running.

Kane, currently in his first season back as the Boilermakers' DC after coaching as an assistant at Minnesota in 2025, said he'll still get players who come in as freshmen without knowing what the A-gap is. Dillon Thieneman, meanwhile, appeared seasoned from the jump.

"Just his demeanor and his approach, how he attacked the drills — there was no learning curve," Kane said.

"So you're like, 'Holy cow, this kid should still be in high school. And he's out here doing better than the kids that have been here in college football for the last two or three years.'"

Thieneman won Big Ten Freshman of the Year that season while establishing himself as Purdue's first All-American DB since 1990. He clocked out with six interceptions, but the Boilermakers were in the basement of the Big Ten. They sank even lower during Thieneman's adversity-worn sophomore campaign, after which he said a difficult goodbye to Purdue.

"Getting to Oregon, one of the main reasons I chose them was, when I was on my visit, they told me exactly what my weaknesses were and what I needed to work on and then their plan for me to get better," Thieneman said.

Thieneman, who is 6-foot and 201 pounds, has been synonymous with speed for years. His first Purdue interception was made possible by him sprinting across the field and plucking a Fresno State deep shot out of the air like a center fielder tracking a fly ball toward the alley.

In the pre-draft process, he ran a 4.35, the fourth-best time of the participating safeties at this year's NFL Combine. But at his position, more than straight-line speed is required.

In part thanks to testing Bolton administered at Oregon, Thieneman sharpened his change of direction. Doing so upgraded his open-field tackling.

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Thieneman went on to reduce his missed tackle rate to a career-low 8.3% while playing a career-high 434 defensive snaps in the box, according to Pro Football Focus.

"I think he became maybe the best open-field tackler in the country his junior year," said Hampton, who was promoted to DC in January after doubling as Oregon's co-defensive coordinator and a secondary coach the past three seasons.

Additionally, Thieneman conceded a mere 145 receiving yards, just 8.1 per reception he gave up, per PFF. He was part of a Ducks unit that ranked 12th in points per game allowed (17.9) and fourth in passing yards per game allowed (157.9) last season. After experiencing a combined five wins at Purdue, he assisted Oregon in piling up 13 in one season, en route to the College Football Playoff semifinals.

"He can do anything, really," Hampton said. "I mean, he can sit in the box. He can play the deep half, he can play in the post, he can cover. He's really a jack of all trades."

Thieneman isn't slowing down, but the game is

Early in training camp, on Aug. 6, Johnson recalled a conversation he had days prior. 

"It's funny. Someone made a comment to me from Tuesday's practice," Johnson said at the time: 'That looked like his Oregon tape. The practice on Tuesday, that looked like his Oregon tape.' It's hard to say that. It was our second day in pads. 

"But you can see that play speed start to show up."

Johnson, though, qualified that anecdote by pointing out that Thieneman was thinking a lot. He's wired to "be on every little thing," the second-year Bears frontman asserted.

"And, so, when you are like that, you can potentially, in your quest to be right every time, slow down," Johnson continued.

The antidote to that mental quicksand? Reps. And more reps.

They're paying off, says Chicago's WR1, Rome Odunze.

Along with extolling Thieneman for being a regular near the top of the Bears' speed board, Odunze said Tuesday that he can tell that the game is indeed slowing down for the rookie. Odunze mentioned an in-breaking route Thieneman invaded to break up a play in camp.

"It's something that takes a little bit of savviness, a little bit of knowing what's happening, seeing the field to accomplish," Odunze said. "So I think the game is slowing down for him a good bit, and he's seeing things a lot quicker."

There was a similar moment in the Bears' preseason opener this past weekend when Thieneman took away a dig from Cleveland Browns quarterback Deshaun Watson. Had Watson thrown the ball there, Thieneman could have made a play on it:

Thieneman's college coaches harp on the fact that he's voracious for the "why" behind his responsibilities within the context of the defense. He isn't just doing what he's instructed to do. He understands why and where his teammates are supposed to be as well.

"It's like a puzzle piece," said Thieneman, who, despite the "Terminator" moniker, can crack the biggest of smiles. "It all fits together. Understanding the man's job next to you helps you understand your job more because you know what he's looking for and then you know what you're looking for."

The homework portion of football hasn't ever bothered Thieneman. Hampton recounted how, unprompted, Thieneman watched Oregon's entire 2024 season when he transferred in. That winter, he took fastidious notes while the Ducks' coaching staff was on the road recruiting.

"By the time we got off the road, he had already studied," Hampton said. "And when we started teaching the defense, he already was acclimated and had an understanding somewhat because he had taught himself."

Recently, he's been forging a relationship with a comparably versatile DB, Cam Lewis, who has filled the vacancy Bryant left at free safety. Whereas Thieneman is a rookie first-round pick, Lewis is a former undrafted free agent in Year 8. He was with the Buffalo Bills the past seven seasons. Along the way, he plugged holes at cornerback, nickel and safety.

In the early days working with Thieneman, a soft-spoken and humble Lewis characterized him as "a natural-born playmaker."

"On a communication aspect, he's been on it. Like, he's really been on it," Lewis also said of Thieneman on Aug. 6.

Together, Thieneman and Lewis will direct traffic as the last line of defense for the Bears. Defensive coordinator Dennis Allen outlined at the start of camp that Chicago must be better in pass defense this season. That's dependent on both pass rush and coverage. Those two are intertwined, with the latter especially falling on a secondary featuring Thieneman.

Chicago led the NFL with 33 takeaways in 2025. It also ranked a pedestrian 22nd in passing yards allowed per game (227.2).

Bears general manager Ryan Poles was looking for more speed in the back end. He got some while bringing aboard a player with "off the charts" football character Poles said in April reminded him of tight end Colston Loveland.

Loveland, the Bears' first-round pick last year, helped ignite Chicago's offense. Thieneman is tasked with learning on the fly to elevate a defense hoping to do its part.

"He's one of one," Bolton said. "Once he's calibrated to where he needs to be in the NFL, it'll be 100%."

Getting to that point will be a race against time. Luckily for the Bears, Thieneman's quick, both with his feet and his mind.