A couple of weeks ago on Ta-Nehisi Coates's Atlantic blog, a commenter posted this clip, of the NFL Hall of Fame corner back Darryl Green running down the Hall of Fame running back Eric Dickerson. If memory serves, at the time this happened, Dickerson was arguably the best running back in the league. Twelve seconds into the clip, you hear play-by-play man Pat Summerall effectively call the TD for Dickerson. If you pause the video there for a moment, and you've spent any time watching football, you can see why Summarall calls out "Goodnight!" at that point: Dickerson, having broken through the secondary, is in the clear. Darryl Green though, in addition to being a great football player, was, at the time of this game (and for much of his 20-year career*) the fastest man in the NFL.
A couple of nice touches at the end of the play: Green taking a second to collect himself after putting everything into that play, and Green and Dickerson congratulating each other as they head back to their respective huddles.
The second-angle replay later in the clip shows that Green didn't even have the best angle of pursuit coming after Dickerson -- Green is aiming too far to the right -- and Dickerson widens the distance a little more by drifting to his left. It doesn't matter: Green corrects and runs Dickerson down. There probably wasn't another man on earth who could have run down Dickerson from the same point on the field.
That's enough of a reason to be impressed by this play. But another reason it impresses me so much is because I've always been such a slow runner. Even as a young and fit high school kid, I was an awful sprinter. If you're an average sized guy and you don't have speed, the most forgiving position for you in high school football is probably inside linebacker, and that position isn't all that forgiving. You can compensate for your lack of speed somewhat by trying to anticipate plays, or by adjusting your angle of pursuit, but only so much. If you don't have speed, all the grit in the world won't do you much good.
Probably the first semi-competent play I made as an aspiring inside linebacker in high school was making a solo tackle on a right sweep play during a JV game. I 'flowed' to my left with the play, but I was afraid if I dived at the ball carrier I'd miss him so I grabbed his jersey and swung him to the ground. The next day at school, during study hall, I sat down at the library table where the JV coach was grading papers. "Coach," I said, "Did you see my tackle last night?". The coach, a 6'5", 300lb+ Irish guy who had been an offensive lineman at an Ivy League school, looked up from the papers he was grading, leaned back, and acted out my unconventional tackle with his hands, indicating he'd seen it, while implying by his facial expressions that I had been surprised that I had caught the guy. Then he said, "You're a linebacker, Dave. You're supposed to make tackles." And he went back to grading his papers.
*One of the related videos that pops up along with this one is of Green running a 4.2 second forty yard dash when he was forty years old. He retired at forty two.