Darius Slay brings his joyful energy to the Eagles. How much does he have left?

Darius Slay is 34 going on 25. Well, not on Wednesdays, he said.

On Wednesdays, Slay still feels every bit his age while the effects of Sunday’s game linger on his body. But his playful personality is immune to any soreness throughout the grind of the season. Slay couldn’t resist calling Quinyon Mitchell “ugly” as he passed the Eagles rookie cornerback in the locker room at his neighboring stall while he was doing an interview.

That ribbing is only fair given how frequently the 23-year-old Mitchell gets on Slay for being the oldest corner on the team.

“All the time,” Mitchell said. “Every chance I get.”

He isn’t the only one. Cooper DeJean, 21, is only three years older than Slay’s oldest child, Darion.

“You could be my father,” DeJean said.

“I’ve told you, I am your pops!” Slay responded. “Know what I’m saying, Coop? Been telling you that. You know what I’m saying? You just came out on the lighter side. You had moved to Iowa with no sun and you just ain’t get no darker.”

Thursday through Sunday, though, Slay said he feels like he’s 25. He claims to look the part among a young cornerbacks corps — “I don’t got no grays like BG,” he quipped within earshot of 36-year-old defensive end Brandon Graham. He exudes the part, too, through his day-to-day zeal for preparing for any given game in his 12th NFL season, according to defensive backs coach Christian Parker.

“He has more energy than the rookies sometimes, to be honest with you,” Parker said. “Just naturally, you know what I mean? So I think he just appreciates the fact that he’s still going.”

And going. In his sixth career postseason appearance, Slay has been more productive than ever, posting an interception, four pass breakups, and nine tackles in his last two games. He still has more left to accomplish. In Sunday’s NFC title contest against the Washington Commanders, Slay will become the oldest cornerback to start in a conference championship game since 2011.

Still, Slay is well aware that his playing career has an expiration date. He said he won’t extend it beyond one more season, and even if he does, he understands it might not be with the Eagles. A victory on Sunday would bring him back to the Super Bowl for perhaps one last chance to add that missing bullet point to his Hall of Fame resume.

His joyful energy — cherished by his teammates, sometimes misunderstood by outsiders — is the reason he’s still going strong at this point in the season and his career.

“I think sometimes people can get it confused, ‘cause he is always in such a jovial mood and a joking mood,” Parker said, “but he’s one of the most prepared players that I’ve been around, just in terms of taking care of himself, taking care of the guys in the room, and just the mental aspect of what he needs to do.”

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Slay has been a “kid at heart” since the Detroit Lions selected him in the second round, No. 36 overall in the 2013 draft out of Mississippi State, Glover Quin said.

The former veteran Lions safety saw that playfulness in the team’s first regular-season game of that season against the Minnesota Vikings. On the Vikings’ first play, Adrian Peterson exploded for a 78-yard touchdown run, with Slay lying in his wake after missing a tackle. The defense returned to the sideline, but the rookie cornerback was not demoralized.

“You never knew if stuff really even bothered him, in a sense, because he was always smiling,” Quin said. “And he didn’t have a problem admitting anything. So he’ll tell you, ‘And AP came through there, and boy, I tell you what. I ain’t never saw nothing like that.’

“Like, he’ll say stuff like that. And that’s just his honest truth, you know what I’m saying? And a lot of guys probably feel the same way. They just wouldn’t say it, right? Slay doesn’t have a problem saying it.”

That’s why Quin and the other veteran defensive backs, including Rashean Mathis and James Ihedigbo, took to Slay so quickly. The young cornerback wasn’t afraid to admit what he didn’t know. He was eager to learn. He didn’t have an ego.

Over a decade, a new team, and six Pro Bowl nods later, Quin still sees those traits in Slay. They were apparent in Slay’s postgame props for the Falcons’ Drake London following the Eagles’ Week 2 loss to Atlanta after the receiver beat the veteran cornerback to catch the game-winning touchdown. Quin can see how that might “rub people the wrong way,” but it doesn’t mean Slay isn’t trying to win.

“If you know Slay, you know how he is, and you’ve got to just live with it,” Quin said. “That’s his personality.”

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His personality is part of the reason for his longevity at the position. Parker explained that cornerbacks are in the spotlight at all times. A player can have 10 perfect plays in a game, but if the 11th doesn’t go his way, people assume he had a bad outing. Slay is evidence that cornerbacks don’t have to “have the mask on all the time” to bounce back from their inevitable missteps.

“Playing such a high-consequential position like he does, you do have to have that short-term memory,” Parker said. “You do have to be able to lock in and be accountable for yourself, so whatever that gets presented as, some guys feed off of talking trash to other people. Some people have a stoic personality all the time. Some people can kind of bounce in between both and kind of be in that flow state where they can come to the sideline and be one way or in the building.

“And then when they put that helmet on, they can really lock it in. And he’s one of those that’s kind of found that balance within himself of how to channel that energy the right way.”

While he keeps it loose, Slay remains locked into the process. He meets with Parker every morning at 7 a.m. before the rest of his teammates arrive at the NovaCare Complex. He watches film and brings his insights to meetings. He takes care of his body throughout the day. He’s never sitting down during practice, even when the offense is on the field, Slay continues to work with Parker off to the side.

The process continues at home, according to his wife, Jenn. He likes to calm his mind for an hour while playing video games — his version of reading “Inner Excellence,” she explained. He gets massages every other day. He gets on his ice machine for 30 minutes afterwards. His at-home routine is all about finding his peace so he can return to the facility ready to start the entire process over again.

“He wants to be pushed,” Parker said. “He wants to practice. He wants more knowledge. It’s a constant pursuit for him. So whenever that road ends for him, that’s his decision. But it’s not like he’s fading into the background.”

» READ MORE: Moro Ojomo gave ‘Inner Excellence’ to A.J. Brown. The lesser-known Eagle has his own motivational story.

Lewis Cine doesn’t typically pay much attention to social media. But in the aftermath of Georgia’s national championship victory over Alabama in January 2022, in which the safety won the defensive MVP award, one of his coaches brought a pair of Slay’s tweets to his attention.

#16 is a ball player!!!

#16 from UGA a DAWG!!!

“He knows game,” said Cine, whom the Eagles signed off the Buffalo Bills’ practice squad earlier this month. “To get that shout-out at that time from him was huge. Like, ‘Oh, [expletive]!’”

Slay knows everyone’s game. He keeps tabs on the up-and-coming defensive backs in college and has worked out in the offseason with some of them, including Avonte Maddox and Sauce Gardner when he was still in Detroit. He had pored over Mitchell’s and DeJean’s college tape by the time they arrived in Philly.

Cine, who was drafted No. 32 overall by the Minnesota Vikings in 2022, would connect with Slay every time he played the Eagles. Even though Slay wasn’t his teammate and he didn’t know him well personally, Cine wasn’t surprised that the veteran cornerback was so friendly.

“What makes Slay a cool dude is he doesn’t act Hollywood,” Cine said. “Like a player his caliber, usually they act Hollywood or like, ‘I’m too good to talk to you.’ Slay’s never been like that.”

It’s Slay’s way of paying it forward after years of soaking in wisdom in Detroit.

In a room rife with first- and second-year players, Slay is “the defensive dad,” Jenn said, channeling his experience of being a father to their five children.

“He takes them up under [his] wing like it’s his kids,” Jenn said. “He takes so much pride in it. He really enjoys teaching these guys. He’s so genuine about it. I don’t think it comes off as a job to him. It’s something he really wants to do. Whether it’s staying after practice, extra time, and really teaching these guys what they need to know. He really enjoys it, and I like seeing that about him, because I watched him do the same with our boys.”

» READ MORE: Darius Slay sees ‘great talent’ in rookie Quinyon Mitchell at Eagles workouts

The young Eagles cornerbacks are taking advantage of Slay’s willingness to guide them. Mitchell, the Eagles’ No. 22 overall pick out of Toledo, said Slay has taught him how to be a professional, on and off the field. DeJean, the Eagles’ second-round pick out of Iowa, leaned on Slay to learn the ins and outs of press-man technique, something he didn’t have much of a basis with at the college level.

Slay doubles as the conduit between Parker and the rookies. Sometimes, if Parker is “on Q’s ass a lot one day,” the coach said, he might ask Slay to deliver a coaching point on his behalf. Parker will also ask Slay to coach up Mitchell when the coach is getting on Slay’s case just to give the veteran a break.

But Slay doesn’t always have to speak for the young defensive backs to appreciate the third-year captain’s leadership. DeJean appreciates the levity that Slay brings to the room, all while holding himself to a high standard of performance.

“Obviously in the game, he’s focused and locked in,” DeJean said. “But he keeps it real light, which is good for us rookies. Kind of showing you that you don’t got to take everything so serious when you’re around the building. We’re playing in the NFL, but you can still have fun.”

» READ MORE: Eagles’ Darius Slay is frankly surprised by the reaction to his podcast hit with Dallas’ Micah Parsons

Whatever they’ve learned from Slay, it’s having a positive effect. Both Mitchell and DeJean are finalists for the Associated Press defensive rookie of the year award, and their stellar play helped elevate the No. 31-ranked defense in passing yards in 2023 to No. 1 in 2024.

“Everything that [Quin] did to me ... I did to them,” Slay said. “And then obviously I panned out pretty well. Hopefully, how they’re playing, they’re going to pan out pretty well, too.”

In the lead-up to the divisional-round game against the Los Angeles Rams, Parker placed an empty gas can at Slay’s locker with an accompanying message scrawled on to a Post-It note.

How much gas do you have left in the Big Play tank?

Parker has left different forms of motivation at his players’ stalls throughout the year. For Slay, he chose an object and a message (featuring a Big Play on his nickname) that could be interpreted in two different ways, either from the perspective of his season or his career.

“We’re kind of in the stretch of the year,” Parker said. “So for whatever’s in that tank, he ain’t got time to refill it down in Houston with the family. We’ve got to empty it out now. Just in terms of his career, just he’s done so much. So how much more does he have left? How much more is he willing to push and continue to do what he’s been doing?”

He proved that he has more left in the tank for the season through his performance against the Rams. Slay finished the night with three pass breakups, tying his 2024 single-game high.

When it comes to his future in an Eagles uniform, though, that gas can could be running low. It wouldn’t be the first time. Slay had revealed on “The Pulp Phiction” podcast in June that he nearly followed his former position coach Dennard Wilson to the Baltimore Ravens when his future with the Eagles was up in the air after the team’s Super Bowl appearance in February 2023.

However, Dom DiSandro had called Slay, asking him to return to the team and agree to a restructured deal. The veteran cornerback signed an extension that runs through 2025. But his final season contains no guaranteed money, so his tank could run dry for real this offseason, at least in Philadelphia.

“I don’t want to,” Slay said. “But if I wanted to do 13, if it got to be somewhere else, it will be. But I don’t want to. I’d love to stay here, do my last year here, for sure. ‘Cause I ain’t doing no other than 13.”

Regardless of what his future holds, Slay is approaching Sunday’s NFC championship game at Lincoln Financial Field with the understanding that it could be his final home game in an Eagles uniform.

“I’m just going to appreciate the moment, just trying to make sure I give this organization the best thing I got,” he said.

After a formative year of learning, laughing, and locking down opposing wide receivers, his young teammates want to do the same for him.

“He is getting old,” Mitchell said with a smile. “So, I want him to get a Super Bowl. I’m playing for him.”

The Eagles host to the Washington Commanders on Sunday in the NFC championship game. Join Eagles beat reporters Olivia Reiner and EJ Smith as they dissect the hottest storylines surrounding the team on Gameday Central, live from Lincoln Financial Field.