Go find a new career. 

That was the expert advice given to Mathias Kiwanuka back in 2010, when several neck and spine specialists told him his best course of action was to pack up the shoulder pads and cleats and be done with football forever. 

“It was very depressing and it was difficult, and when I got that clearance to come back, literally the sun came back out and I never looked back after that,’’ Kiwanuka told The Post on Thursday. 

Kiwaunka as a defensive end played four more seasons stalking quarterbacks for the Giants. He can relate to what Daniel Jones is going through, waiting each week for scans to be taken and read before a determination is made to give or deny medical clearance. Jones on Sunday will miss his third consecutive game with what the Giants are calling a strained neck, an injury that first surfaced after he took a hit while sliding after a designed run on Nov. 28 against the Eagles. 

Kiwanuka does not know the specifics of Jones’ neck issue, but he does have firsthand knowledge of how the Giants operate under the direction of Ronnie Barnes, the team’s senior vice president of medical services. 

“The Giants don’t ever mess around,’’ Kiwanuka said. “Ronnie Barnes does not mess around when it comes to your health. It’s all about the person, not the player and what your quality of life is going to be like after the fact. In my mind, they’re going to err on the side of caution. 

“Other teams would probably clear him — not probably, a lot of other teams would clear him sooner than the Giants would, I know that. I was told, ‘You can go play somewhere else even if the Giants don’t clear you’. The Giants will not medically clear you because it’s a moral thing for them, it’s not just about whether or not he’ll be healthy enough to play, they want to know you’re going to be healthy when you retire and get done playing.’’ 

Kiwanuka played the first three games in 2010 and had four sacks before his season was curtailed, shockingly. He had been feeling tingling and numbness in his arms for some time. He avoided going to the mall, because walking around for 30 minutes while holding a few bags made his arms go numb. He would awaken from a restless sleep and his entire body, from his chest down, would be numb, and his ex-wife would have to sit him up, attempting to loosen his neck enough so he could regain feeling. 

He would get or give a hit in a game and come away with what they used to call “a stinger.’’ Pain would shoot through his body, but the pain he could deal with. 

“But when you start to go numb, that’s when you start to go, ‘Oh crap,’ ’’ Kiwanuka said. “You can’t physically move parts of your body, you’re locked up.’’ 

Kiwanuka walked off the field after the Week 3 loss to the Titans at MetLife Stadium and knew he could not continue this way. The Giants flew him around the country, seeking the opinions of several neck and spine specialists. He was diagnosed with disc herniations and spinal stenosis and given an injection to try to alleviate the inflammation. He was inactive for the next four games before the decision was finally made to shut him down. 

“I saw all the best doctors and got their opinion and one by one they all told me, ‘Hey son, you should probably find a new career,’ ’’ Kiwanuka said. “But I was stubborn enough at that time, I wanted to play ball and I was willing to wait it out.’’ 

Kiwanuka played through the 2014 season and won a second Super Bowl. Other teammates, linebacker Antonio Pierce and running back David Wilson, were not as fortunate. Both had their NFL careers cut short by neck-related ailments — Wilson after only 21 games. 

Kiwanuka knows Jones is able to run and throw and practice with the Giants and that gives him confidence this scenario is not as serious as the one he went through. 

“My best guess, seeing him out there throwing the ball, my best guess is he’s fine and it’s just the Giants being the Giants,’’ Kiwanuka said. “They’re gonna err on the side of an abundance of caution and I can tell you honestly it wouldn’t matter if there was a Super Bowl on the line or not. If his health was in question at all, Ronnie Barnes would do what’s best for him in the long run. They’re not gonna mess around with your neck. I think he will be fine and I think they would have taken much stronger action if it was something very severe.’’