PHILADELPHIA − Sometimes you just know.

Jordan Davis knew, calling Eagles defensive tackle Fletcher Cox "a pillar" and saying that he's "in mourning" because Cox won't be returning for a 13th season.

Cox himself did not address his future Wednesday, saying, "I haven’t thought about anything."

But the signs were there, literally and figuratively.

Cox had already cleaned out his locker when he spoke to the media Wednesday afternoon, although he said that was a coincidence. "I needed to get it cleaned, so today I had enough time to do the job."

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Cox was saying this while standing at his locker with an A.J. Brown-signed jersey hanging next to him. Brown wrote in the white part of the No. 11: "Thanks for sharing the field with me. Eagles legend!"

With that, a new era on the Eagles' defensive line is about to begin. Cox was the Eagles' first-round pick in 2012, and defensive end Brandon Graham was their first-rounder in 2010. The two, along with center Jason Kelce, are not expected to return in 2024.

Kelce reportedly told teammates after the Eagles' 32-9 loss to Tampa Bay in the wild-card game Monday night that he's retiring. A day later, Kelce said on his podcast that he hasn't made up his mind yet.

The three are atop the Eagles' leaderboard in games played. Cox and Graham are both in the top five in team history in sacks − Graham is fourth with 73; Cox is fifth with 70.

Davis, in his second season, and Jalen Carter, just finishing up his first, are expected to replace Cox and Graham as leaders of the defensive line. Davis said that reality has hit him hard.

"I knew it was coming, but I didn’t know it was going to come this early," Davis said about Cox. "When you watch a guy growing up, he’s kind of like your hero. I got a chance to work with him every day. I’m very fortunate. We got to see him walk away. Granted, he walked away on his own terms a lot better than a lot of people can say in this league.

"But we had to watch him walk away. It kind of hurts to see this. It hurts me more so because I didn’t get the chance to send him out the right way. I didn’t get to send him out riding into the sunset. It’s kind of like, we crashed and burned, and he's got to limp out. He's got to crawl out."

For the record, Davis said Cox didn't officially say he wasn't returning, and Graham himself said Monday night that he'd like to return to the Eagles in 2024 for a 15th and final season. But Graham is turning 36 in April, and there's a good chance that the Eagles will want to get younger after Graham had just three sacks this season.

Graham, no doubt, can see the proverbial writing on the wall, just as Cox can. The Eagles used first-round picks on Davis and Carter in 2022 and 2023, respectively. And Cox knows that it's time for them to play after both Cox and Graham served as mentors.

"Obviously, they drafted some young talent, and those guys are really good," Cox said. "They’ve come a long way since they got here. Jordan and Jalen, they did a really good job of taking on the game, learning how to be a pro. Do they have room to grow? Yes. Everybody has room to grow. Even after 12 years, I always have room to grow."

Then Cox was asked what the key is for the next phase of their development.

"Just continue to grow," Cox said. "The biggest thing for those two guys is showing up in shape at OTAs (in May), and not being behind the 8-ball. Obviously, it’ll be Year 3 for Jordan, Year 2 for (Carter). You’ll be able to see younger players make that jump between those two years.

"I think the next level for them is to be not afraid to be great. Those two boys, they got a chance to be really great, especially in this league."

Sure, Cox said there's a chance he could stay for another season with the Eagles, but reiterated that he hasn't thought that far ahead.

The Eagles have signed Cox to one-year deals for less money each offseason after allowing him to become a free agent. The difference is Cox, 33, could be looking for a two-year deal, and that might have to happen elsewhere.

Perhaps the Eagles are ready to turn the defensive tackle position over to Davis and Carter anyway.

Carter had six sacks, tied for the second most by an Eagles rookie in team history. Davis, who's 6-foot-6, 340 pounds, improved drastically from his rookie season, both in his play and in his conditioning. Davis played 45% of the defensive snaps this season, up from 20% last season, and he had 2½ sacks after not having any as a rookie.

But Davis also admitted, "My body is beat, I can tell y'all that for sure."

"It's a long season, a long grind," he added. "But at the end of the day, I know what it takes. I have to do even more. ... I definitely got better from last year. I plan to get better next year. That's something me and Jalen (Carter) were just talking about, how are we going to take care of this team, take care of the D-line.

"We can't use Fletch as our security blanket because he's not there anymore. So there's definitely a lot of maturing that has to go into this offseason. ... It's a lot of pressure. I'm not going to sit here and sugarcoat it.

"I think we're going to create diamonds next year instead of busted pipes."

Then Davis started talking about Cox again in the past tense. He got wistful and stopped himself, saying he was starting to get emotional.

"Of course, we can call him," Davis said. "He's not dead or anything."

Contact Martin Frank at mfrank@delawareonline.com. Follow on X @Mfranknfl.

This article originally appeared on Delaware News Journal: Eagles Fletcher Cox isn't returning; Jordan Davis, Jalen Carter know why