Peyton Manning has been playing without feeling in his fingers for 4 years

Peyton Manning's late-career recovery from multiple neck surgeries continues to be one of the more underrated stories in the NFL.

Manning missed the entire 2011 season - his final year with the Indianapolis Colts - after undergoing a spinal fusion surgery to fix a damaged disc in his neck. After that, he had to completely re-learn how to throw a football at age 36.

This isn't a situation where he had an injury and then recovered 100%. Manning told Peter King of the MMQB that he hasn't had feeling in his fingertips of his throwing hand since the neck surgeries. He said:

"I can't feel anything in my fingertips. It's crazy. I've talked to a doctor recently who said, Don't count on the feeling coming back. It was hard for me for about two years, because one doctor told me I could wake up any morning and it might come back. So you wake up every day thinking, Today's the day! Then it's not."

Manning told Sally Jenkins of the Washington Post that he couldn't throw a ball 10 yards in his first post-surgery passing attempt.

"It's hard to explain but I kind of lost awareness of my arm in space," he told Jenkins about what it was like when he tried to throw after his surgery. "When you had the same throwing motion for so long - golfers talk about repeating their swing, well, quarterbacks repeat too. But I couldn't repeat. That was scary. Just discouraging."

After months of training - much of it behind closed doors - Manning improved enough to where he could continue his NFL career. He signed with Denver in 2012, and has won 12 games in each of his three seasons with the team.

It's hard enough to do what Manning is doing at age 39 under normal circumstances. It's extraordinary that he's still playing at such a high level after an injury that very well could have ended his career.