At 35 years old, in his 15th season with the Dallas Cowboys, how does he keep producing the way he does?

The NFL might be a young man’s game, but after two games, nobody in the NFL had more catches than Witten (17).

It is the most catches Witten has had in the first two games in his career. His 156 yards is the third highest he’s had after two games. His two touchdowns match the best start of his career.

Surely there is something genetic that has allowed him to play 221 straight games, the longest current streak in football for a position player and the most in team history. There is some luck, too.

But Witten steals a line from golf legend Ben Hogan: The secret is in the dirt.

It’s the work not only during the week but during the offseason.

Every year since 2003, his rookie season, Witten has driven into Valley Ranch or The Star and known his athletic trainers, Jim Maurer, Britt Brown and Greg Gaither, have been there waiting for him. Since 2011, head strength coach Mike Woicik and assistant Brett Bech have been with Witten.

“My car never pulls in that facility early in the morning or leaves late at night and their cars aren’t there,” Witten said.

“I know they’re not going to try to feed me stuff that’s not true or sell me on a new pitch. People say, ‘Where do you go train?’ I train here. ‘Who do you look to help you play?’ These are my guys. I have a lot confidence in that. It’s what they’ve done in their careers and their experience, but more than that, I know they’re going to be honest with me and come up with the best plan for me.”

For years, the Cowboys attempted to get him to take time off during organized team activities, minicamp and training camp. He finally relented this offseason, not practicing three straight days. Coach Jason Garrett’s message did not change from when they first broached the idea years ago.

“I think I was in a different place,” Witten said. “We were 8-8 three years in a row, coming up short. I just didn’t think it was the time. And I was relatively young four years ago, just turning 31.”

But to call them off days is a misnomer. He might not have been on the practice field running routes, but he was still working out in the weight room under the watchful eye of Woicik, who has six Super Bowl rings.

“One of the best things about him is he’s seen veteran players have success,” Witten said. “Michael Irvin said there’s no way possible he would’ve played at that level at the end if not for Mike Woicik, so I believe that. You see the guys in New England: Tedy Bruschi, Willie McGinest, Troy Brown. Even Tom [Brady]. For him it’s not just made-up numbers. There’s numbers he looks to through the offseason to show you’re reaching those standards. It’s not just an eye exam, ‘Hey, he looks good.’ He’s kind of the godfather of it all.”

More than two hours before every game, Bech stretches Witten, looking to increase his hip flexibility. During the week, Maurer, Brown and Gaither are organizing his treatments and maintenance programs.

Maurer is in his 28th season with the Cowboys and has not had many — if any — players like Witten. There have been times he’s asked Witten how he does it.

“It’s pretty amazing,” Maurer said. “In a lot of cases, it’s mental fortitude and all those catch-phrase words. He’s a tough guy, but he also listens and does what he’s asked to do and that helps the process along.”

Witten signed a four-year extension this offseason, but he has become a year-to-year player, much the same way Tony Gonzalez became a year-to-year player at the end of his career. There have been considerations for age, like how much he lifts and how many times a week he lifts. He has become more conscious of his flexibility and core. He watches what he eats. He even makes sure he gets enough sleep.

“The best thing about our plan is not what we say. It’s what we do,” Witten said. “It’s not some tricked-up secret. The secret is in the dirt. The secret is in the repetition of going back and doing it over and over and over. Many people look at it and say, “Wow, it’s good,’ but it’s evolved every year. And then the results come and it allows me to play at a high level. That is a byproduct of what we do.

“To be able to go do it every year, it takes everybody. I’m certainly appreciative of the investment everybody has made in me.”

In the spring, Witten’s sons, C.J. and Cooper, had a field day at their school Witten did not want to miss. With his tenure on the roster, he could have missed one of the voluntary workouts and nobody would have said a word.

Instead of skipping the workout, he was at The Star by 5 a.m. after a 40-minute drive from his house.

His car was not the first in the parking lot.

“There’s guys that have moments,” Bech said, “but for him to do it and sustain it for such a long period of time, he probably stands at the top of the hill, if you would ask me.”