CHARLOTTE, N.C. -- Ryan Kalil put his socks on the same way for his first 146 NFL games. Then on Sunday, his final home game for the Carolina Panthers, the five-time Pro Bowl center realized he was doing it wrong.

"I always thought the logo went on the bottom," Kalil said on Sunday as he held his son, Cade, in front of his corner locker after a 24-10 loss to Atlanta. "Today I had a thought to myself; this was flawed in how the seam was on the bottom of the toes. Somebody pointed out the logo goes on the top.

"So, you're never too old to learn something."

Kalil, 33, made the decision before the season that this would be his last. He decided to go out on his own terms, something not every professional athlete gets to do because of salary-cap decisions, health or a decline in performance.

So he knows Sunday's finale in New Orleans (1 p.m. ET, Fox) will be his last.

For other players, there is uncertainty. Outside linebacker Thomas Davis, 35, wants to return for a 15th season, but management has yet to give him an indication that another contract will be offered.

Defensive end Julius Peppers, 38 and an almost certain first ballot Hall of Famer, won't commit to what he wants to do in 2019. Like Davis, that could depend on whether management wants him back.

Among his final words on Sunday when Carolina (6-9) officially was eliminated from playoff contention, Peppers said, "It's always disappointing whenever you don't make the playoffs. But there's always next year." But, will there be a next year?

And then there is coach Ron Rivera, whose team is on a seven-game losing streak after a 6-2 start. Although there's a feeling Rivera will return for a ninth season, owner David Tepper hasn't given a public vote of confidence to the two-time NFL Coach of the Year.

The only one of these four certain about his future is Kalil, who will go down as one of the best linemen in team history.

"He means everything," Peppers said of Kalil. "One of the greatest teammates I ever played with. A professional guy. Very selfless. A great example for everyone to learn from. This organization is going to miss him. I wish him the best."

Not as planned

Kalil had high hopes for 2018 as he's had for every season, including 2012 when he took out a full page ad in The Charlotte Observer in July guaranteeing a Super Bowl victory. The Panthers finished 7-9.

But this season in particular Kalil was excited because he believed the talent was here to make a run at the Super Bowl and because he was playing with his younger brother, left tackle Matt.

Matt was placed on injured reserve before the season with a knee injury and never recovered enough to return. Then came the seven-game losing streak that ended those postseason hopes.

"Disappointing," Ryan Kalil said. "I think that's the best word to describe it."

There's been nothing disappointing about Kalil's career except for falling short of winning a Super Bowl. Since arriving here as a second-round pick out of Southern California in 2007, he has established himself as one of the best centers in the league.

"When I first got into the league, I had never played center before and my line coach in Green Bay put his film on and said, 'This is how you play center,'" left guard Greg Van Roten recalled of his 2012 rookie year. "Then to come here last year and be around him and learn from him, it was surreal. To play next to him this year, it was awesome."

"His experience and presence is invaluable. You can't replace it. We just hopefully, without him next year, can keep the tradition going."

Kalil's performance was only a fraction of his worth to the Panthers. His leadership in the locker room and in the community is where the 6-foot-2, 300-pound California native most excelled.

"A lot of time[s] when I'm talking to Ryan, I feel like I'm talking to a peer as much as I'm talking to a player," Rivera said. "He's a very bright and worldly young man.

"Communicating with him, his whole focus was about helping us be better as a football team. That I really do appreciate. It's one of those things you look at somebody and you see where they've gone in their career and you know where they go afterwards is going to be just as good if not better."

Kalil's next step likely will revolve around his production company he formed in Los Angeles. He has already worked with stars such as Will Ferrell and Dwayne "The Rock" Johnson.

His in-house spoofs, such as the one where the offensive lineman mocked Cam Newton's exotic birthday vacation in Central America with a North Carolina lake trip, are legendary.

All these things are why Kalil can say without hesitation that his NFL journey "way exceeded my expectations."

"I was a guy who in college had several coaches tell me I would be too small to play at the next level," Kalil said. "Twelve seasons later, I leave with a lesson: Nobody defines you but you. Hopefully, I played that forward to the younger guys."

Farewell thoughts

Kalil's final gesture as he left Bank of America Stadium on Sunday was a wave to the stands. It wasn't so much for the fans but to his family who all came to see his home swan song.

"Not how I wanted to remember it, but very appreciative to all the fans," Kalil said of going out on a losing note. "This whole community has been great to me and my family. I leave this place with a full heart. Very blessed to be a part of it."

Peppers looked into the stands as he left, perhaps an indication he expected this to be his last home game.

Davis is the wild card. He has made it clear he doesn't want to play for any team but Carolina, which made him a first-round pick out of Georgia in 2005. He also has made it clear he wants to leave on his own terms as Kalil is, leaving the door open for another organization.

"Hopefully, it don't come to that," Davis said. "I think I played pretty well. I don't think I've done things to go out and hurt this football team. I've been a contributing factor. It's going to be totally up to them on how they deal with it.

"If they want me back, that'll say I played pretty well. If they don't, then I didn't do a good enough job."

Rivera has to walk a delicate line here. He says he wants Davis to return but understands the business side will be a factor.

That's another wild card. If this is Rivera's last game Sunday, it won't be the first time he's been unable to leave on his own terms. His career as a linebacker for the Chicago Bears ended earlier than he wanted in 1992.

While Kalil has reminisced heading into his final game, Rivera is focused on beating New Orleans and avoiding the distinction of being the first coach of a team that has gone from 6-2 to 6-10. He says everyone is being evaluated, including himself.

Rivera is certain about one thing, and that's what Kalil brought to the organization. So is Davis.

"Ryan is a potential Hall of Fame player to me," Davis said. "That's what he's been to this football team, that's what he's been in this league. To see him make that decision, you have nothing but respect for him. He felt like it's time for him. Hats off to him. He's had a helluva career."

Even if he did put his socks on backward for 12 years.