The oldest non-kicker to play Sunday in the Giants-Cowboys game was a 35-year-old Running back.

Seriously? In today’s youth-crazed NFL?

Let’s explain: Taiwan Jones is listed on the Giants’ roster as a running back, but he hasn’t actually carried the ball since 2019.

In fact, he only has 53 rushes over a 12-year career that has staying power because of his special teams prowess.

“When players come into the league, we expect to play the roles we played in college,” Jones told The Post. “It just wasn’t the case for me, but I had older guys take me by the arm and let me know that if I embraced special teams I could play a long time. And they were right.”

Jones, signed to the Giants’ practice squad on Aug. 31, was elevated to be a starting gunner and jammer on punts.

“A lot of respect any time a guy can play that long because it’s hard to do in this league,” said Matt Breida, the Giants’ No. 2 running back and personal protector on punts. “Because he’s one of the top gunners in the league, they are going to have to vice him — and that’s fewer rushers inside. You can’t single that guy — or whoever is against him is probably going to lose.”

Jones knew general manager Joe Schoen, head coach Brian Daboll and several teammates from two stops with the Bills (2017-18 and 2020-22).

“I just try to be a plus in any locker room I’m in,” Jones said. “I want to bring out the energy, not just for myself but for my teammates.”

The Giants are shorthanded on special teams because their backup receivers don’t offer much coverage experience and rookie Bryce Ford-Wheaton is sidelined after working as a gunner in training camp.

Jones played 305 special teams snaps last season.

“To be a good gunner, you have to have confidence. Speed helps. And be relentless,” Jones said. “Every time I go out there with the mindset that I’m the best person on the field, and it’s my job to prove that.”

A player can be elevated from the practice squad three times before he must be added to the 53-man roster for a fourth game.

That’s where Jones wants to be — like Pro Bowl specialist Justin Hardee is for the Jets.

“It’s Year 13, so I pretty much have an understanding of why teams want me,” Jones said. “Daboll was really transparent and said, ‘I’ll never tell a guy that he has a position.’ He told me it’s up to me to win a job. Any time I get the opportunity to compete, that excites me.”

Jones credits Rock Cartwright — a seldom-used running back who carved out a 10-year career on special teams — for setting his path.

“More than half my career, what kept me going was the thought that I was going to get an opportunity to play running back,” Jones said. “Special teams is mano-a-mano, who’s better? When I’m in a corner, I’m really focused on trying to win.

“I’m not just here just to be part of a roster. I want to make a difference and help out the offense or defense.”

The Giants had to use Saquon Barkley at quarterback after Daniel Jones and Tyrod Taylor were injured in the same game last season.

What would happen in a hypothetical crisis in which Barkley and the other three running backs all were unavailable?

“Oh, I’m still ready,” Jones quipped. “Put me in, coach!”