Could Junior's shot at title be last, best chance?

He’ll turn 40 one day before the Bank of America 500 at Charlotte Motor Speedway, the fifth of 10 postseason races. Despite his remarkable season that consists of three wins (second-most in the series) and 11 top-fives (tied for most in the series) and the No. 3 seed entering the Chase for the NASCAR Sprint Cup, Earnhardt realizes there’s always the chance he’s closer to the end of his career peak than he is the beginning — or even the middle.

He knows there’s something about age thresholds for any athlete, that there eventually comes a time when your body and mind can no longer do what it once did.

“I’ve always wondered what happens to a person physically and mentally that changes their performance over time,” Earnhardt said during Chase Media Day. “As their career goes further into their 40s, some people are fast still — (like) Mark Martin and Harry Gant. It’s something inside. It’s a passion to do the details, to do the extra work. I don’t know. I just wonder, do you know it’s happening where you’re falling off and not competitive anymore?

“I’ve often wanted to talk to other drivers like, ‘What’s that experience like when you go through the past few years of your career. Why do you think your career changed?’ We’re running great and I feel like I’m driving as well as I ever have, so I’m not too worried about it personally right now, but there’s going to come a day where I’ll have to make a serious decision about what I want to do with my career. Hopefully it won’t be for a few years.”

Earnhardt Jr. can look to Hendrick Motorsports teammate Jeff Gordon if he needs a pick-me-up. At age 43, Gordon is a championship contender and has rebounded from a pair of sub-par years — at least by his own lofty standards — when whispers began about whether he had lost the touch, whatever “the touch” actually means.

Still, Earnhardt’s insight Thursday demonstrated that the driver knows for every Gordon success story, there’s another driver who steadily declined once crossing the 40-axis.

Want more pressure? Earnhardt knows he has the support — and at times, weight — of Junior Nation clamoring for that elusive silver trophy.

“I know that we have a huge, very supportive fan base,” Earnhardt said. “I’ve been reading all year long on Twitter and hearing the comments at the track to me directly. ‘Oh, this is the year, we’re gonna do it. You’re gonna do it.’ I can definitely sense that urgency. This is as close as I think the fan base feels like we’ve gotten to winning a championship. They really believe in it, so I know there’s a lot of people out there that want it to happen and there will be a bunch of people out there disappointed if it doesn’t.”

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