COSTA MESA, Calif. — Such an interesting ball cap.

Worn and weathered, it undoubtedly has been around the Chargers longer than most of their players and coaches. Once it was deep black; now it's faded and splotched with gray. If hats could talk, it could tell some stories.

Written across the front of it is a Latin phrase. It translates to, "Now I begin."

A few years back, this was the Chargers' motto. It was on the wall of their locker room and on the chests of their players.

A priest friend of Philip Rivers introduced the idea to him long ago, and he has carried it with him since, as a quarterback and as a man. "It's a never-ending beginning," says Rivers, who wears the hat throughout his days. "You are always beginning again and again and again."

If he has just thrown a touchdown pass, he begins again, working toward the next one on the sidelines. If he has just lost a heartbreaking game, he begins again, studying the next week's opponent.

He is in his 15th NFL season, with 51,028 passing yards behind him and nowhere near as many in front of him, but he begins again, to be his best, like he did when he was a rookie.

Most people would consider this stage of Rivers' career a closure. Not Rivers.

As he prepares to match passes with young Rams quarterback Jared Goff in a battle for Los Angeles on Sunday, the concept of beginning again has never resonated more with Rivers.

"Nunc coepi," Rivers says, mixing Alabama drawl with the classical language. "I must begin again."

Beginning again isn't always easy.

It wasn't easy in 2010. After a 13-3 regular-season record, the Chargers lost 17-14 to the Jets in the first round of the playoffs at home when Nate Kaeding missed three field-goal attempts.

It wasn't easy after losing in the divisional round of the playoffs in 2007 to the Patriots. The Chargers were the top seed in the AFC after finishing the regular season 14-2. They were loaded with 11 Pro Bowlers, including the NFL's Most Valuable Player, LaDainian Tomlinson. They led for most of the game until Tom Brady led a surge that gave the Patriots a three-point lead with 1:10 left. Rivers brought the Chargers to the 36-yard line, but Kaeding missed a 54-yard field-goal attempt. The Chargers lost 24-21.

It wasn't easy in 2008 after losing the AFC Championship Game. Rivers tore his ACL in the divisional playoff game and had a hush-hush arthroscopic surgery between games. He put a brace on his leg and went out and threw 37 passes, leading a team of wounded warriors in one of the most courageous performances in NFL history. The Chargers scored only four field goals in a 21-12 loss to Brady's Patriots.

Gene J. Puskar/Associated Press

"Who in their right mind would be able to do what he did in that game?" says former teammate Eric Weddle, one of his best friends in football. "It tells you how much he loves the game. I don't know that I've ever been around a teammate who loves the game as much as he does."

Ask Rivers what he is most proud of in his career, and he will tell you it is that he has not missed a single start since he replaced Drew Brees as the Chargers' starter in 2006, his third season. It has been a most difficult achievement. "Sometimes his ribs would pop out the day of the game or the day before, and he'd be in the most excruciating pain," Weddle says. "He couldn't move. But he'd get it shot up and play."

The NFL record Rivers most reveres belongs to Brett Favre: 297 straight starts. With 194 straight, Rivers is fourth all-time. If he keeps it going, he will move into second place on the list next September. But with much more sand in the bottom half of his hourglass than the top, Rivers concedes the crown will remain Favre's.

Favre is one of eight quarterbacks who have thrown for more yards than Rivers. Peyton Manning's record of 71,940 yards is more than 20,000 yards away. Rivers concedes that record is out of reach as well, especially with active quarterbacks Brees, Brady, Eli Manning and Ben Roethlisberger also ahead of him.

One thing that he does not concede is out of reach is a Super Bowl ring. All the most transcendent quarterbacks of Rivers' era—Brady, Brees, Favre, both Mannings, Aaron Rodgers, Roethlisberger, Kurt Warner and Russell Wilson—have at least one.

It is the only thing missing from Rivers' bio. And as the years pass, that blank space seems to get bigger and bigger.

"It's something we talk about," says Chargers tight end Antonio Gates.

Rivers and Gates have been teammates Rivers' entire career. Gates joined the Chargers one year before Rivers and refers to Rivers as "my baby."

"It would be the stamp on his career and the stamp on my career," Gates says. "When you think about all the greats who played for a long time, you think about the ones who won a Super Bowl ring. That's why you see the fire in him. That's why you see the competitive edge and the drive he has, because that's something he still needs to fulfill."

Jeff Gross/Getty Images

Rivers will tell you a career is about more than a Super Bowl, though. He points to the teammates he has touched and been touched by: Gates, Weddle, Tomlinson, Kellen Clemens, Malcom Floyd, Nick Hardwick, Jacob Hester and Danny Woodhead. He will tell you he knows he has given his all, so he has nothing to regret.

He does, however, wonder how many more real chances he will have.

"It doesn't eat at me," he says. "As a competitor, it drives you. It's hard to say this without someone saying, 'Golly, he doesn't care that much.' I want to win a championship for our team, for our organization. I want us to win one bad. But do I lose sleep over it? Or would I be miserable one day if I never did it? The answer is no."

Rivers has no scars from the 2006, 2007 and 2009 seasons. He doesn't curse his luck.

He just begins. Again.

"We've had some missed opportunities when we didn't get it done when we should have," Rivers says. "But each and every year, you start new on a climb to try to get to the mountaintop. You push forward and begin again."

Rivers has never attended a Super Bowl. He hopes his first will be as a participant—in Atlanta next February.

There are those who will tell you he has an excellent chance. Analysts Dan Patrick, James Jones and Tomlinson were among many who picked the Chargers to make it to Atlanta. As of Monday, the Chargers had the ninth-best chance of winning the Super Bowl at +2000, per OddsShark.

"Shoot, I think we have a heck of an opportunity," Rivers says. "We got a chance. I like where our team is at."

He likes where he is at, too. In his past nine games, going back to last season, Rivers has a 109.6 passer rating. He has averaged 325.8 passing yards and 13.1 yards per completion in those games. He didn't throw an interception in seven of the nine games.

He will be 37 in December—an age when many quarterbacks are in a state of deterioration. But if he is declining in any way, he's hiding it well. "It doesn't seem like he's aging," Chargers offensive coordinator Ken Whisenhunt says.

Rick Scuteri/Associated Press

Rivers' age may be showing in his demeanor more than in his abilities. He still is one of the more fiery and demonstrative quarterbacks on any given Sunday, but he has more forbearance these days. "I definitely have calmed down," he says. "The emotions have been a little tempered."

More than ever, Rivers seems like he belongs to a previous generation of players. There really isn't anyone like him in his locker room, or even in the league. He uses the word "golly." He has been vocal about his Catholic faith and belief in natural family planning (he and wife Tiffany, his high school sweetheart, have eight children, and he says more are in the plans). His wardrobe would fit in better at a square dance than at a team party.

"He has the worst fashion ever," Weddle says, laughing. "His bolo tie and the old grandpa jacket that probably cost $75. He never buys anything new other than maybe some cowboy boots. That's him. He's not into pleasing people by the way he looks. I respect that."

He looks best when it matters. When he's wearing navy, gold and white, or powder blue, gold and white, depending on the Sunday.

In the autumn of his career, Rivers isn't fighting time. He's going along with it. And he seems to be his best version of himself. "The last half of last year and the beginning of this year, there has been a steadiness, a calmness," he says. "I feel like I'm seeing things good. I'm in a good place mentally with the offense and with what we're trying to get done."

Whisenhunt's offense flatters Rivers, as it once did Warner. And the players around Rivers are bringing out his best.

Rivers has had outstanding skill position players around him before. But he believes he has more useful weapons now than ever.

"When you talk about the skill guys, there's so many," he says. "We have the speed of Travis [Benjamin] and Tyrell [Williams]. Big Mike [Williams] is coming along, doing a nice job. Keenan [Allen], look at the player he has turned into, one of the top guys in the league. We have the tight ends with Gates back in the fold and Virgil Green. The backs Austin [Ekeler] and Melvin [Gordon] complement each other so well. They're both very good runners, but they're great at catching the ball out of the backfield.

Gordon, Allen and Rivers Kelvin Kuo/Associated Press

"It's such a dynamic group and a versatile group. Who knows who it's going to be any week? They can't just key in on Keenan, or key in on Melvin. That's what makes us dangerous."

If Rivers is better than ever—and so far in 2018, he has career highs in yards per game (340.0), completion percentage (73.1) and rating (119.6), with six touchdowns and only one interception—those players will have something to do with it.

"We have guys who can do multiple things for him," Whisenhunt says. "That allows him to do a lot of different things, which is right in his wheelhouse because he can process and handle all of those things. So I don't think he has been pressing to feel he has to make the play. He knows if this guy is not here, he's got this guy, or he's got that guy."

That's why Rivers feels so good this September.

Gates had been thinking that 2017 would be his last NFL season. The Chargers told him they were moving on. But Rivers texted him throughout the offseason and camp when he was sitting it out, asking him when he was coming back. Finally, he showed up the week before the season began.

He and Rivers wanted to begin again, together. "We have a chance," Gates says. "Let's make the most of it. You never know when it's your last chance. That's how I feel. And that's how he feels."

Somewhere, there is a high school football field. Maybe it's in Alabama, near Rivers' high school. Maybe it's in Southern California.

It's waiting for Rivers. It's calling him.

He has not pinpointed when he will walk away from the NFL, but within five years, he plans on being on that field with a whistle around his neck.

Rivers' oldest son, 10-year-old Gunner, is in fourth grade. He throws the ball with the same motion as his father.

It is Rivers' intent to be Gunner's coach when Gunner gets to high school. "That will give you a range right there," he says in answer to the question about how much longer he will play.

Weddle believes his friend is as excited about coaching high school as he is about playing. Rivers just says: "Brady and those guys keep talking about playing until they are 45. You don't have to worry about me being there then. I can tell you that for sure. I don't want to shut it down too early. But I'm also not into trying to go until it's too late."

Other than Gates, all of his teammates who were contemporaries are gone, most having moved to the next phases of their lives. Even his team has moved, from San Diego to L.A.

When the Chargers headed north last year, Rivers chose to remain in San Diego and commute. He is driven more than an hour each way in a $200,000 SUV/mobile office equipped with a 40-inch screen, satellite television, Wi-Fi and a refrigerator. It's one of the many ways things have changed over time.

Rivers doesn't have to be reminded that the pages of his life are turning faster than ever. His oldest daughter, Halle, is 16. Some of the quarterbacks he's opposing are much closer to her age than his. This season he's already gone against Patrick Mahomes and Josh Allen, both 22, and admired their young arms.

Harry How/Getty Images

Other next-gen QBs he is scheduled to oppose this year are Goff (23), Jimmy Garoppolo (26), Derek Carr (27), Marcus Mariota (24) and maybe Baker Mayfield (23) and Josh Rosen (21) if they get promotions.

"I don't know that I see it as a changing of the guard," he says. "There are still a lot of us older guys that have some time left. But [Goff] is one of a bunch of young guys that are gonna be around a long time, well after I'm gone."

They're just beginning their careers. Rivers is beginning again. But this beginning is special to him.

"I like to think I haven't taken any of it for granted," he says. "But when you are on this backstretch, I've tried to appreciate it more, be more aware. The practice days, the walkthroughs, the bus rides—all those things you can't come back to. When you are getting into Year 15, you think about it. This thing is going to come to an end at some point. I think I am more grateful daily."

There is more at stake for Rivers now than a Lombardi Trophy. There also is the matter of how he will be remembered.

If he wins a Super Bowl late in his career, will he ascend to the level of John Elway in our mind's eye?

If he peters out, will he be thought of as Ken Anderson, a player with flashy statistics who many think was a cut below some others from his generation?

Perhaps the player Rivers will forever be most compared to is Eli Manning, whom the Chargers traded to the Giants for Rivers and two draft picks. Rivers' career has been better than Manning's by many measures, but not by one important one: Manning has two Super Bowl rings.

Quarterbacks are judged by rings. Rivers understands. "It comes with the position," he says. "Head coach and quarterback have a record attached to them. And I have always felt a great responsibility to help lead our team to win games, the division and ultimately the Super Bowl. We haven't been able to accomplish the latter yet. Gonna keep pushing like crazy to get to the mountaintop."

With a Super Bowl ring, Rivers would be a cinch for the Pro Football Hall of Fame. Without one, whether he has done enough is debatable.

Adrian Kraus/Associated Press

When Rivers was a boy, he had posters on his wall of Elway, Favre, Troy Aikman, Peyton Manning, Dan Marino and Joe Montana. It would mean something for him to stand on a stage with them, wearing matching jackets. But it would not mean everything.

"I've always watched the Hall of Fame speeches," he says. "Thought about what I would talk about if I ever was up there. But I don't wake up in the morning thinking about wanting to be in the Hall of Fame. I really don't."

He is unencumbered by the weight of what we will think. He has thoughts of his own.

This is how Rivers wants to be remembered: "A guy that played with great passion, could be depended on…was a good teammate…and that would compete 'til the end no matter what the situation," he says.

That's all.

And with that, he is off to replace his ball cap with a helmet, to begin again.

Dan Pompei covers the NFL for Bleacher Report. Follow him on Twitter: @danpompei.