You wanna separate the men from the boys? Put them on a football field in January. In Minnesota. That’s where my teammates and I found ourselves in the wild-card round of the playoffs last season. Six below, –25° windchill.

A few plays into the game, my visor was frozen over and fogged up, so I could barely see. I lined up across from a wide receiver on a small sliver of the field that was still in the sun. The rest of the field, from the numbers closest to me to the far sideline, was under the stadium’s shadow. When the ball was snapped, I felt the receiver engage me and then push off.

Screen!

I looked into the shadows toward the quarterback and I couldn’t see anything. Between the sun and the fog on my frozen visor, I was blind. It was like I was staring straight into a sheet of ice.

But below the frost, through the bottom of my face mask, I could see the receiver’s legs — his purple and white socks popped off the green turf. I had watched the Vikings run this screen pass a few times on film, and I did a quick calculation in my head and figured that the ball should be coming in right about … now. So I reached out and grabbed the receiver.

My timing was perfect. I hit him just as the ball got there and he dropped the pass.

Incomplete.

I remember that so well because it was a pretty crazy play. I was basically blind, and I had to rely on my other instincts — as well as my preparation, which helped me to both recognize the play and nail its timing — to break up the pass.

But the most difficult part of that play wasn’t trying to see through my visor or battling the sun.

It was everything that happened before it.

I often get asked the same questions by fans and media. Here are three that you might guess would come up pretty regularly:

What’s the most difficult part of your job? Who’s the best corner in the game, besides yourself? Who’s the toughest wide receiver to cover?

I understand why I get asked these questions, but I never have good answers for them because they’re too complicated to explain in sound bites. There are a lot of aspects of my job that are difficult. And there should be — otherwise, anybody could do it. But while you can compare players, you also have to respect the unique abilities and the individual traits that separate them. Those are the things that make them great.

You wouldn’t put LeBron James in a three-point contest against Steph Curry and say that Steph is the better player if he wins, just like you wouldn’t say that Allen Iverson was better than Shaq because AI had a crossover and Shaq didn’t. It’s a more nuanced discussion — even when you’re comparing football players, and especially when you’re comparing guys who play the same position, like cornerbacks.

So if you’ve ever asked me, or wanted to ask me, about the most difficult part of playing corner, or about the best corners and toughest receivers in the game, read up. The answers — at least from my perspective — are mostly here.

I’ll start with the first question — the one about the most difficult part of my job — right where I left off, in Minnesota on that January day.

A few plays before the ice-blind screen breakup, on the first play of the game, I had come up from my corner position in run support and put a hit on Adrian Peterson, who in those conditions was basically a glacier barreling down the field. I came up from the backside, made the tackle in the backfield and landed on the frozen turf, hard.

Those things stick with you — sometimes for a few plays, but sometimes for an entire game.

So if I had to pinpoint the most difficult part of my job, I would say that it’s not any one thing I do on any given play.

It’s doing all of it, every play.

I never come off the field when we’re on defense. That’s more a fact of life for a lot of defensive players in the NFL than it is just for a corner — linebackers only sub out occasionally, and some never do. I’m in there every play, whether the ball comes my way or not.

You may not see it on your TV screen at home because the camera always follows the ball, but if the play is away from me, and I’ve got a fresh backup receiver across from me whose job is to take off down the field and run me away from the play, I have to respect his route. I have to run with him, full speed, like he’s the No. 1 receiver and he’s getting the ball — because there’s always a chance he might. And if I get three different fresh guys off the bench running me off on consecutive plays, and I come back up to the line against their true No. 1 in a crucial situation where I know they like to hit him on a fade, I can’t stop the game and say, “Hold up, I gotta catch my breath.…”

Nope.

I have to match up — and man up — against their best receiver and do my damn job.

No excuses.

As corners, we never leave the game. That’s part of the challenge.

It’s also all part of the chess match.

In the NFL, winning has a lot more to do with survival than it does talent. Because not only can I not be tired, I can’t show that I’m tired. The eye in the sky never lies. And if an offensive coordinator up in the coaches’ box sees me limping up to the line, or with my hands on my knees sucking wind, guess where the next play is going?

So when I line up in subzero temperatures for the seventh straight play and I’m dinged up from a couple of hits before, it doesn’t matter if I’m across from a guy who’s fresh off the bench and who I can’t even see.

It’s still me against him, and one of us has to make a play.

My job is to make sure it’s me.

That said, let’s talk about cornerbacks a little bit.

Everybody wants to compare us. But like I said, it’s not that simple. There are subtle nuances to playing the cornerback position that go unnoticed by the general eye. When you flip channels to any game on Sunday, you see a cornerback line up against a wide receiver — maybe the corner is up on the line playing press, maybe he’s playing off. After that, once the ball is snapped, a lot of what happens looks the same.

But if you zoom in, you’ll notice different techniques that separate even the most elite corners.

Let’s look at a comparison a lot of people have made in recent years:

Richard Sherman vs. Darrelle Revis.

Revis and I both play at the line of scrimmage, but he plays it totally different than I do. People look at us and say, “They’re both at the line of scrimmage, so they’re both playing press. So it’s the same.”

That’s what it looks like — but we’re actually playing two different versions of press.

Revis uses a technique some corners call soft-shoeing. It’s where you stand at the line of scrimmage — in press — and slowly shuffle back off the line at the snap and mirror the receiver. It’s a pretty common way of playing press, and Revis is very adept at it.

The technique we use in Seattle is a little different. Ours is more of a true press. Some people call it a read-step, or a kick-step. The real difference is that it’s more aggressive than soft-shoeing. Instead of backpedaling and mirroring the receiver, we stand in there. We don’t give. We don’t take a step until the receiver’s first movement, and then we kick back in the direction the receiver releases. If you guess wrong, and you kick the wrong way, you’re kind of done. You’ll have a lot of ground to make up. So that instinctive first step at the line of scrimmage is crucial.

Most guys would be terrified to play our technique because we don’t move. We get our hands on the receiver right at the line, and we stay in his pocket throughout the play — we don’t wait to see where he’s going to go before we get on his hip.

But that’s what I do well. I’m stepping and kicking, and Revis is soft-shoeing. That’s one of the reasons it’s so difficult to compare us. My technique doesn’t work for him, and his doesn’t work for me. It’s just two different ways to skin a cat.

Then you got a guy like Aqib Talib in Denver, who plays a good read-step like we do, but who can also soft-shoe. At 6’ 1’’, he’s tall. He’s also quick, fast and physical, so he can even play off the receiver and still be effective because he has the tools to attack from a few yards off the ball without any give.

Or think about Chris Harris Jr., who plays alongside him, and who plays the off-technique as well as anybody. He’s not the biggest guy in the world — I think he’s 5’ 10′, 200 pounds — but he thrives playing that off-technique and relying on his instincts to anticipate and put himself in position to make a play. There’s a lot of studying and natural talent that goes into playing that brand of cornerback.

But no matter what technique you play, you have to have an incredible amount of respect for a guy like Patrick Peterson, who has tremendous athletic ability. Some of the freaky things he can do, other elite corners will look at and say, “There’s no way my body could do that.”

There was one play against the Jets a few years ago where he was covering on a post and he got beat. I mean, the receiver had at least two steps on him. He was rolling, with no safety over the top.

But once the ball was in the air, you could see Pat just close the gap, and….

Bang.

He jumped right over the receiver’s head and stole the ball.

It was an incredible play that he shouldn’t have been able to get away with. It should have been a touchdown. It didn’t get a lot of recognition on SportsCenter’s Top 10 or anything, but as a corner, you see a play like that, and you appreciate it. You appreciate it because you’ve been in that situation. You understand what it takes to make a play like that — the fight, the moving parts, the level of difficulty.

When I was growing up, I used to watch guys like Deion Sanders, Charles Woodson, Rod Woodson — guys who went and got the ball.

Patrick Peterson is one of those guys.

Some of the freaky things [Patrick Peterson] can do, other elite corners will look at and say, ‘There’s no way my body could do that.’ Richard Sherman

There’s also a hand-fighting element to playing cornerback that nobody talks about. I mentioned soft-shoeing vs. the read-step, but that’s in the feet, where it all starts. The second aspect of playing cornerback is the hand-fighting.

As a corner, you technically have five yards to use your hands. After that, you have to live with the consequences and make the best of it.

That’s why the hands are so important.

There’s an art to hand-fighting. When receivers and corners get into it, especially in press coverage, hands fly. People can talk about pass interference or illegal contact all they want, but inside of a route, both the receiver’s and the corner’s hands are constantly moving. Each will push and pull — whatever the situation dictates — within those motions to gain position. To the casual observer (and even to referees at times) all this action goes mostly unnoticed. But the great receivers will always be able to get away with it, and the great corners will always be able to combat it. It’s only a split second, but it can be the difference between a pass completion, an interception or a pass breakup. Part of it is strength, but there’s also a fluidity to it — on both sides of the ball — to where you don’t get flagged.

It has to look natural. That’s the trick.

Revis is pretty good at hand-fighting. I’m pretty adept at it myself — I have to be with the kind of read-step coverage we play. But Antonio Cromartie, when he was at his best, was really good at it.

So if you’re trying to pinpoint the best corner in the league, you have to take all these details into consideration. You can’t just go off the eye test, because there’s so much more to what we do than what you see on TV on Sunday. I’m not one to rank other players, but the guys I mentioned here are the ones that stand out to me.

I participated in the Tribune Mailbag series recently in which I answered a few questions from fans. If you noticed, I didn’t answer any of the three most commonly asked questions — the ones I laid out when we started here today. That’s because, like I said, the answers a little more nuanced and require a deeper explanation that can’t be articulated in a sound bite, or even a short-form response.

Today, I didn’t answer the question about the toughest receiver to cover, but I’ll answer that in due time. That’s another one of those nuanced discussions I can’t just slide in a quick answer for.

But I’d be remiss if I didn’t mention the preparation that goes into doing my job.

I know it goes without saying, but as cornerbacks — and I guess as NFL players in general — we study a ton of film. Ad nauseam. Until our eyes hurt.

You probably remember the 2013 NFC championship game when we beat the 49ers — you know, the game where I batted the ball away at the last second to set up the game-sealing interception and send the Seahawks to the Super Bowl.

Forget what I said after the play — I know I have, and I’ve already acknowledged that I shouldn’t have called out the 49ers’ wide receiver in the manner in which I did.

Instead, look at the play.

At the time, there were a few things that I understood: I understood that the 49ers were driving. I understood the momentum. I understood the situation, and from studying film, I understood what they liked to do in that situation.

And the double move was number one on their list.

I made that play because I saw it coming. Because I was prepared. And I had been banged up — run off on the plays before that one and used up on the the drives earlier in the game. When you get to the fourth quarter, nobody is 100%. That’s when ballers ball. That’s when stars shine. So no matter what had happened previously, the reality was that it was first-and-10, fourth quarter, inside two minutes, and it was me vs. the 49ers’ wide receiver, and one of us had to make a play.

My job was to make sure it was me.

And that’s what I did.

When it comes to playing cornerback, you’re on an island out there. It doesn’t matter if you’re hurt or you’re tired, if there’s a –25° windchill or if the NFC championship is on the line. At the end of the day, the only thing that matters is….

Can you make a play?