Tyrann Mathieu’s effect on the Chiefs’ defense is still felt to this day

NFL rosters are ever-evolving, living entities. Whether it's from injuries, the salary cap or Father Time, they're always changing. The 53-man roster with which a team begins the season is never the same when Week 18 arrives — and from one season to the next, a roster can be completely different.

But once in a while, a player comes along who can leave a lasting impact on a team — one that remains long after he's moved on.

That's the effect New Orleans Saints safety Tyrann Mathieu had on the Kansas City Chiefs while he was with the team from 2019 through 2021.

This became evident during the preseason, when Kansas City's general manager Brett Veach revealed that he and Mathieu have remained friends who still text each other . That's how Veach learned Mathieu approved of the team's acquisition of rookie defensive back Jaden Hicks in last spring's NFL Draft.

"I was at home watching some preseason games after we got done playing one night," Veach recounted. "I just randomly texted Tyrann Mathieu to check in and say hi. We were exchanging texts — and he kind of ended it with, 'And [number] 21 is a stud.'"

Remember: Veach is the man who decided to let Mathieu walk when his contract ran out in 2022. In life — or in business — it's rare for an employer and employee to remain friends after the employee has been let go.

But that speaks to the kind of player, person (and leader) Mathieu is. More than two years after his departure, you can still see his impact on how Kansas City's defensive backs go about their business.

"I got a special place in my heart for Tyrann," admitted defensive coordinator Steve Spagnuolo on Friday — before revealing something that happens with assistant coaches Dave Merritt and David D'Alesio before practice begins.

"Usually about 10 minutes before that, all of the DBs are out on the field. They're doing footwork; Dave's with them and Donald's with them. But that was really established with Tyrann all the way back [then]. He was pulling those guys out of the locker room 10 minutes early.

"That's a little leadership thing. I think he laid a foundation here — especially in the secondary — of some of the things that we do [today], quite frankly."

After Mathieu left, the ripples of his mentorship continued through players like L'Jarius Sneed and Trent McDuffie.

"When he was first here, LJ was young at the time," added Spagnuolo. "I remember him learning from Tyrann — and then [when] Tyrann left, LJ was teaching Trent. So there's been a trickle-down — and I think we owe Tyrann a lot for what he did when he was here."

Players like defensive end Chris Jones also noticed.

"He was such a leader," Jones told reporters on Friday. "One of the premier safeties in this league — and still playing at a high level to this day; I think he's defeating Father Time also.

"But Tyrann has always been an exceptional leader — even coming out of LSU . [When] you put on the tape, there's one player that always sticks out — and that's Tyrann Mathieu."

Mathieu left nothing less than a legacy in Kansas City. So when the Chiefs host the Saints for "Monday Night Football" — and you see McDuffie mirror a receiver's footwork perfectly, turning at just the right moment to bat a pass away — you can tip your cap to Mathieu on the New Orleans sideline. Even though he's found a new NFL home, he played a lasting role in establishing Kansas City's championship defense.