To Steve Kerr, it was a no-brainer.

The Golden State Warriors' incoming coach knew it helped a team's morale to see the best player doing the dirty work of playing defense. He had an offensive wonder determined to become the best player in the game. And he had a defensive guru -- assistant coach Ron Adams -- in his ear.

"He was a really melded player already," Adams said of Stephen Curry. "But there was always a caveat. As in, he didn't have to defend his position. I think if you want to be the best, and he wants to be the best, you have to do both things."

So two weeks after his hire, Kerr spoke to Curry over lunch in the Bay Area and explained that the team's practice of hiding their top scorer on defense was over.

Curry would have to D up.

It wasn't exactly a hard sell. "He wants to be challenged," Kerr frequently said of his superstar. It's something Steph's father, Dell, had told Kerr over the summer, and it's something Kerr keeps coming back to when discussing his point guard's growth.

And to the surprise of many, it has more than worked. Thanks to some clever new defensive principles, and despite his spindly frame, Curry has blossomed to become one of the NBA's most effective defenders -- ranking fifth among point guards in defensive real plus-minus. According to Synergy Sports, the opponents he guards have shot just 36.8 percent on the season. He's averaging a career high in steals and a career low in fouls.

He's even frustrating top-caliber opponents. Who knew that the stronger-looking Russell Westbrook struggled with Curry defending him this season? In three games against Curry, Westbrook shot far below his averages, at 32.9 percent from the field and 26.3 percent from deep.

Curry doesn't look like a prototypical defender. He's skinny, not especially long and unathletic enough that it's a surprise every time he dunks. But according to defensive real plus-minus, he has a more positive impact than more celebrated defenders such as Rajon Rondo, Avery Bradley his teammate Shaun Livingston. And RPM suggests his defense is the best in the league among MVP-caliber guards, ahead of James Harden, Chris Paul or Damian Lillard.

According to the numbers, Curry positively impacts the Warriors' defensive efficiency more than any of his backcourt teammates -- yes, even Klay Thompson, who drew the tougher assignments under Mark Jackson -- and ranks second among all guards in the league at opponents' field goal percentage.

It was all born of some subtle shifts in his defensive game. This is the story of how he's doing it.

1. High Hands

When you ask scouts about Curry's defensive abilities, praise comes in the form of alliteration: high hands. Offensively, Curry shoots the ball quicker than closeouts can figure. He's just as much a quick draw on defense, flipping passes out of the air with goalie reflexes. Curry gets a lot of deflections out of the pick-and-roll on overhead passes. It's the kind of pass he likes to throw and the kind of pass that, for years, defenses targeted for steals. Now he's giving the league a taste of its own medicine.

"I'm fighting over the screen, and I'm watching. As soon as he picks the ball up, I still have time to react, get a hand up," Curry said. "That's what they used to do with me when I used to turn it over all the time. So, I figure why not do it to them too?"

2. The Strip

Those hands that shoot up so quickly in passing lanes come back down with the force of a chef's cleaver. It's visible on this strip of a Westbrook drive:

In the past, Curry was too quick to go for the strip, getting out of position and reaching. These days, Curry deploys the strip judiciously, usually when he's right in front of the offensive player. Shot selection is to offense as strip selection is to defense.

"That's just footwork," Curry said. "If you could stay in front of him, use your body. I used to get into trouble, being so antsy to get a steal as opposed to just playing defense and forcing a tough shot. I got a steal there, but I don't have to strip the ball or get a deflection every possession. It's nice if I can do it, but like on that play, if I can keep him out of the paint, or keep my body in front of him, make him shoot over the top, percentages drop tremendously."

3. Pressure

When asked what Curry has improved upon the most defensively, Kerr was quick to say "ball pressure." Once a liability, he's now on the offensive when he's on defense. He's fourth in steals per game and trails only Kawhi Leonard and Jimmy Butler in steals per foul.

According to Curry, keeping a guy to one side of the floor is what Adams emphasizes most of all. A man must be contained to be pressured. (It's why Lyndon B. Johnson cornered politicians before leaning into them and extracting concessions.) In this instance, Curry pulls it off by beating Tony Parker to the spot when Parker attempts to probe the lane.

"Once they commit to one side, it's easier to guard half the floor than it is to guard the whole court," Curry said. "So once [Parker] gets committed, standing on the high side, you take away his options. I got lucky on that reach. Quick hands when he exposed the ball. You have to keep him on one side of the floor."

4. The Sneaks

"You got to be in help position already," Curry said. "You can't start chest to chest with your man. From there, it's about knowing the other team's options."

Curry's referring to a well-timed defensive sequence in which Harrison Barnes fronts the post and Andrew Bogut arrives right on the catch. When the trap is set, there are only so many options.

"As soon as you see the trap and the guy's back to you, he only has a few options and you hope you guess right," Curry explained. "He's either going to throw it there where I get the steal or throw it back to Bledsoe over here and I can close out and get back to my man. So, either way, we're in good shape."

It's not gambling if it works. The risks Curry takes on defense are more like card counting than spinning the roulette wheel. As Andre Iguodala said of Curry, "He knows the ball can only go certain ways."

Assistant coach Adams adds: "When we get two on the ball we try to triangle up behind the ball. So [Curry's] basically in his proper position, just reads it and goes."

Adams has a particular vision for Curry's defense: He wants Stephen Curry to be the next John Stockton.

Adams said "Stockton knew what the other team was going to do, knew how to gum up an offense. I've talked to Steph about this before. He has these natural abilities on the ball and away from the ball and in guarding catch-shoot players coming off pins. He's good at all of that stuff. Now if you can add that aspect of just understanding what every team is trying to do, and the times he does that, he breaks plays up inside of himself."

To channel a player from the past, Curry must consistently see the future. That sounds like a difficult challenge, but Iguodala sees heightened foresight in Curry's future: "With more time in the league you learn more tricks of the trade. You're going to see more sets. His game's just evolving. He's getting better."

5. The Connection

Ask Curry about a play, almost any play, and he can remember, visualize and explain it with remarkable ease. I showed this particular clip to him for a few seconds, then accidently closed the window.

"It doesn't matter," Curry said before instantly recounting: "Draymond stunted the ball, gives me time to recover, and then at that point I got to get my high hands up so there's not a quick pass back to the top of the key, and that sort of messes J.J. [Redick] up because he thinks he has a good outlet but I take it away and then he picks his dribble up and it's over."

The Clippers are employing a dribble handoff -- an increasingly popular offensive tool that the Warriors typically crush. The relationship between Curry and Green is symbiotic here.

"I know if I fight over the top of a dribble handoff, my big's supposed to stunt and help me for a second and get back to his man and I'm supposed to fight over and get back in front of my man," Curry said. "If Draymond doesn't do his job there, J.J. can turn the corner and get to the basket and then you might say I'm a bad defender because I let J.J. score."

Green has similar expectations of Curry in these situations. A defensive player of the year candidate this season, Green espouses that a guard's role is the most important aspect of guarding the dribble handoff: "No. 1 is the guard staying attached. When the guard is attached, as a big, they give you so much leeway."

This play is an especially precarious situation for the Warriors. If Curry is late around the screen, it's an open 3-pointer for the sharp-shooting Redick. If Green doesn't track DeAndre Jordan, it's a lob to a far larger player. Everyone must play their role, right down to Harrison Barnes on the weakside, who's attentive enough to snag an errant pass after crashing down to block Jordan's path. Curry has improved defensively, but that improvement cannot exist in a vacuum.

6. Post-weakness

Per the play above, Curry said, "You can use your arm bar long as you don't extend it and just try to keep him from going middle because most of the time my help's coming from the baseline."

On Synergy, Stephen Curry ranks in the 98th percentile in post defense. Somehow, he was the defender on two Dirk Nowitzki post-ups, and each time the shot resulted in a shank. It's a small sample size and Curry is certainly no reliable bulwark against the Enes Kanters of this world, but when tested in the post, he's ready.

He's ready in part because he has been targeted this way for so long. "My first two years, the scouting report, even point guards tried to post up if they had a little size advantage," Curry recalled. Most of Curry's post defense is preventive, though. He's skilled at fronting bigger players and batting the ball away. "I'm just sitting low, making sure it's a tough pass over the top. When I'm fronting, there's supposed to be a big guy in the back that can show his arms and body to deter that pass."

7. The Spins

This play looks like silliness before it's a steal.

When I first noticed Curry trying this, I wrote it off as bad defense. He was spinning off screens, which I equated with getting lost. Then it kept happening. And happening. Stranger still, these plays tended to work out for the defense, far more than I would have expected.

"Darren Erman taught me that, to be honest with you," Curry said, referencing Golden State's since-fired defensive expert. (Erman and Adams both favor spinning. Erman had long been a friend and admirer of Tom Thibodeau and Adams was Thibodeau's right-hand man in Chicago.)

"If you get hit square on a screen, it's a longer route to fight over instead of spinning under. It's a more efficient move too, because either they're going to hold you and it's a more evident illegal screen, or you're going to get under and off their body pretty quick." Matchups and positioning matter here. Spinning can work if you're far enough away and if your man can't capably shoot quickly over the top of a screen.

Spinning is never Plan A, but in Adams' teachings, it's far more acceptable than dying on a screen when you can't get over the top. (This is why the famously unscreenable Kirk Hinrich, a former student of Adams, is inclined to spin frequently. It's part of an ethos: You're never allowed to quit on a defensive possession. Ever.)

"It's similar to rebounding," Adams said. "If you block me off, I can be content to stay behind you and smell your deodorant, or I can choose to spin off of you. And spinning, almost invariably you get to semi-equal position." This is where Adams, normally steady with his words, goes double negative, his voice rising. "That spin is just part of that mindset of, there is no time that you cannot be pursuing. There is no time that you cannot be in the play."

The act takes a second and it contains multitudes. Spinning is unideal, a surrender, an evasion, a stoic acceptance of responsibility, and a surprise all in one whirl. What starts off bad is transmogrified into good. In Adams' world, the literal 360 is the metaphorical 180.

The Warriors challenged their top player to get better, and it worked. They're having the best regular season -- in terms of point differential -- we've witnessed since Jordan's Bulls.

The notion of Curry as defensive ace might be subversive, but perhaps not as subversive as the next statement: Curry got better not just because he wants to be the best player alive, but also because he thinks it's within his reach. "He wants to be the best," Kerr said. "He knew that to be the best he had to be better at that end."

Even as Curry is favored to win an MVP award, the concept of a skinny, 6-3 point guard as league alpha strikes people strangely. That spot is usually reserved for physical freaks like LeBron James and Kevin Durant. It all just smacks of basketball heresy.

Curry's star continues to rise in defiance of convention, though. He markets himself as "the patron saint of the underdog" for a reason. Curry doesn't look like a good defensive player, but then again, he never looked like a Division I college player, he never looked like an NBA draft pick, and he never looked like an NBA superstar. But he has accomplished all of those things. If reputations are often based on appearances, Curry aims to forge a reputation as someone who transcends that expectation. And his aim is excellent.