Four Bills' Players Whose Stock Is Silently Soaring on Defense

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Training camp is in full swing this summer in Pittsford, New York, and the Buffalo Bills will soon be headed back to their new home along Abbott Road in Orchard Park, New York, to finish out the remainder of this critical offseason under first-year head coach Joe Brady.
With that said, let’s take a look at a few under-the-radar players who have been silently rising up the roster ranks at St. John Fisher University.
CB Kani Walker
Height: 6-foot-2; Weight: 204 lbs; Age: 23; Year: R; College: Arkansas

Outside of linebacker Kaleb Elarms-Orr and EDGE defender T.J. Parker, undrafted rookie defensive back Kani Walker might be the next rookie in line when it comes to who’s made the most noise at training camp so far amongst this year’s crop of youngsters from the 2026 draft class.
While he technically wasn’t selected on any of the three days during the league-wide event in April this spring, the 6-foot-2, 204-pound cornerback has certainly fit right in with the rest of the 10-player rookie class in terms of assimilating himself in Western New York.
In fact, he’s stood out amongst other drafted players at his position like seventh-round pick Toriano Pride Jr. and second-round pick Davison Igbinosun.
Igbinosun, or “IGB” as everyone calls him, has rightfully gotten more run with second-teamers and some spot duty with the starters at times, but Walker has managed to shine any chance that he’s been given an opportunity.

Buffalo hasn’t signed any notable veterans like former longtime cornerback Tre’Davious White yet, and Walker’s performance through two weeks of practices in Pittsford, New York, might be the reason why.
Keep an eye out for him in the preseason. The former Razorback defender might sneak his way onto the roster as a fourth boundary corner for the Bills with a solid string of performances later this month.
S Geno Stone
Height: 5-foot-11; Weight: 207 lbs; Age: 27; Year: 7; College: Iowa

Veteran safety Geno Stone might not be making a ton of splash plays so far at St. John Fisher University, but he’s been consistent.
And, with fellow safety C.J. Gardner-Johnson now sidelined for the foreseeable future with an apparent calf strain, Stone has been getting plenty of opportunities to run with the starting unit in defensive coordinator Jim Leonhard’s new scheme.
At first, it was rookie Jalon Kilgore who was starting to shine in Gardner-Johnson’s abrupt absence from camp, but it has since shifted to mostly being a toss up between Stone and longtime Bills’ veteran Damar Hamlin running with the first group on defense.
We’ll see if Stone can start making any noise with the added opportunities.
Newly signed #Bills S Geno Stone on why he chose Buffalo, cites relationships with fellow former Iowa Hawkeyes Micah Hyde and A.J. Epenesa in his decision-making.
— Andy Young (@AndyYoungTV) March 16, 2026
"Me getting back into a winning culture...having Josh Allen on the other side of the ball." pic.twitter.com/1jAEH0GWiV
The 5-foot-11, 207-pound defender once had a total of seven interceptions in a single season back with the Baltimore Ravens in 2023. Stone also had 68 total tackles and nine pass deflections to go along with his tremendous takeaway tally that year.
So, clearly, he’s a capable backup even if his time in Cincinnati over the past few seasons weren’t as smooth as when he was a Raven.
I’m sure his new defensive coordinator—a former safety who played 10 seasons in the National Football League—can course correct anything that Stone might be struggling with if he’s needed to start at any point this season.

It’s CJGJ’s job to lose when he returns from injury—whenever that is—but Stone has so far cemented himself as a top reserve in training camp through two weeks. That could change, though.
We’ll see.
ILB Keonta Jenkins
Height: 6-foot-2; Weight: 211 lbs; Age: 24; Year: 2; College: Virginia Tech

The past few years at training camp it’s been fellow linebacker Joe Andreessen, a.k.a. “Buffalo Joe”, who was the talk of the town in terms of an undrafted player making noise at the second-level of Buffalo’s defense.
This year—although not as beloved by fans as Andreessen—former 2024 undrafted linebacker Keonta Jenkins has been standing out for his positive play in Pittsford, New York.
He’s not producing at the level of rookie fourth-round pick Kaleb Elarms-Orr, who is getting several starting reps beside veteran Terrel Bernard in camp, but Jenkins has filled in at times within the starting unit, which is nothing to take lightly.
We’ll see if the former Hokie can go from being a practice squad player in 2025 to becoming a member of the 53-man roster in 2026.
There’s a tiny logjam at the position, but we’ll soon find out who shakes loose later this summer once the team heads home from St. John Fisher University.
DT Phidarian Mathis
Height: 6-foot-4; Weight: 312 lbs; Age: 28; Year: 5; College: Alabama

Heading into the summer, all of the smoke surrounding the defensive tackle position in Buffalo revolved around players like Deone Walker, Ed Oliver, and DeWayne Carter.
And for good reason.
Walker and Oliver are expected to take giant leaps forward in Leonhard’s new 3-4 defense this upcoming season, while Carter made quite the transformation to his body this offseason in order to finally make an impact for the franchise that made him a third-round pick out of Duke University three springs ago.
Each of those players has still received recognition through the first week and change of training camp in the greater Rochester, New York, area, but there’s been another player at the position who’s silently had a quality camp.

Walker was kept out of the padded practices on Monday and Tuesday due to an apparent left elbow injury, and it was Mathis—not Carter or fellow nose tackle Zion Logue—who stepped in with the starting unit.
A former 2022 second-round pick of Washington out of Alabama, Mathis has a solid ability to anchor from the nose tackle position despite being only 312 pounds.
He also has the pedigree given his previous draft status when coming out of college. So, we’ll see if he can keep stacking days at camp.
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John W. Green is a contributor for Bills ON SI after previously working for USA TODAY Sports Media Group’s Bills Wire, as well as the Buffalo FAMbase blog. He is a former sports reporter for the Press-Republican daily newspaper in New York’s Champlain Valley covering local high school, collegiate, and semi-professional sports for three counties. A former associate sports editor for SUNY Plattsburgh’s student-run newspaper, Cardinal Points, which was inducted into the Associated Collegiate Press H.O.F. in 2010, John covered the school’s 2014 D-III NCAA national champion women’s hockey team. John is also the editor of BILLieve in Buffalo on Medium.com. He has a bachelor’s degree in newspaper and multimedia journalism from SUNY Plattsburgh.
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