This story appears in the March 14, 2016, issue of Sports Illustrated. To subscribe, click here.

His name evokes an island, warm and remote, enchanting and unspoiled. Though Kawhi Leonard was not named after Kauai, the garden isle on the northwest tip of the Hawaiian archipelago, he believes his father liked the sound of the place. Kauai is lush and bountiful, yet subdued compared with some of its overstated cousins to the south. Kawhi has never been. Someday he'd like to go.

He was the baby of the family, minded by four older sisters, who stood in long lines to buy his Air Jordans and prophesied in home videos his athletic feats. At seven, Kawhi interrupted an annual physical to inform his pediatrician that he planned to play in the NBA. "Do you know how many kids come in this office and say that?" the doctor smirked. It is possible that Kawhi has not uttered an audacious word since.

He quietly observed his older sisters, immersed in their adolescent dramas, and avoided any of his own. He called coaches and parents sir and ma'am. He handed footballs to officials after touchdowns. He passed basketballs to friends instead of shooting them himself. "Why do you do that?" his mother, Kim Robertson, once asked him.

Leonard watched Come Fly with Me, a glossy 1980s documentary about Michael Jordan, until his eyes ached. But the promise of movies, commercials, stratospheric stats and double-pump highlights—trappings of success in the post-Jordan age—were not what enticed him. "I don't like to bring attention to myself," he says now. "I don't like to make a scene." Basketball was an outlet, not a showcase, a vehicle for escape rather than glory.

"I could be on the court for two hours and it felt like 10 minutes," Leonard says. "It made time go by." Math, his favorite subject, produced a similar effect. He could lose himself in geometry homework, calculating angles and solving problems, not having to deal with big crowds or nosy questions.

"So many people care so much about being popular," says Jeremy Castleberry, who grew up with Leonard. "He never did."

As an unassuming sophomore at Canyon Springs High in Moreno Valley, Calif., Kawhi declined to correct a reporter who kept awarding his points to a teammate. "Doesn't matter," Leonard told his mom. As a senior at Martin Luther King High in Riverside, he blew off the Nike camp when his peers would have cut up their Kobes for an invitation. "I don't need the exposure," he told his AAU coach, Marvin Lea. He ruled out UCLA and USC because San Diego State recruited him first. Still, he was difficult for Aztecs coaches to reach over the phone, leaving them perpetually panicked that he'd renege.

When the Spurs acquired Leonard out of SDSU in 2011, through a draft-day trade with the Pacers, they flew him to San Antonio for a meeting with coach Gregg Popovich. "He was as serious as a heart attack," Popovich recalls. Needless to say, they hit it off, and Leonard slid comfortably into the Spurs' hardwood monastery.

A lot has changed for Leonard since that conversation with Pop—he was named Finals MVP in 2014, captured Defensive Player of the Year in '15 and this season seized the unofficial title of best two-way player in the NBA—but a lot hasn't. Leonard spends his summers in a two-bedroom apartment in San Diego, where he hangs a mini hoop over one door so he can play 21 against Castleberry. He carries a basketball in his backpack even when he isn't going to the gym. He often drives a rehabbed '97 Chevy Tahoe, nicknamed Gas Guzzler, which he drove across Southern California's Inland Empire as a teenager. "It runs," Leonard explains, "and it's paid off."

He is the only star still rocking cornrows, an outdated tribute to Carmelo Anthony, and he shrugs when friends claim he'd expand his endorsement portfolio if he shaved the braids. He is happy to sponsor Wingstop, which sends him coupons for free wings, so he can feed his Mango Habanero addiction. This winter, after his $94 million contract kicked in, he panicked when he lost his coupons. Wingstop generously replenished his supply.

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"You'd think we were talking about a starving journeyman in the D-League," says Randy Shelton, San Diego State's strength and conditioning coach, who trains Leonard every off-season. But the player's hunger is real. He is the rare professional athlete who distinguishes between greatness and stardom. "He wants the greatness badly," Popovich says. "He doesn't give a damn about the stardom." You won't find him on Twitter, Facebook or Instagram. You probably won't catch him in a photo shoot, on a red carpet or at an awards ceremony, even if he is the guest of honor. Check that—especially if he is the guest of honor. "He loves the game," Popovich continues. "He ignores the rest of it."

Leonard ambles into arenas apart from the group, absent the standard-issue headphones, the custom suit, the shiny jewelry. "If [the arena] were empty," Popovich says, "he'd probably like it a lot more." He wears a black hoodie, True Religion jeans and a thousand-yard stare. He is 24 but looks significantly older, like a man with a mortgage heading to the graveyard shift. "I'd rather play than be in an office doing paperwork," Leonard says.

The hard labor occurs in the quiet strip between the paint and the perimeter. Leonard drops into his stance, bent at the waist and the knees, arms outstretched and palms parallel to the floor. He looks like he is surfing. His head swivels from the guy with the ball to the guy in the corner and back again. He gauges angles and cuts them off. Some opponents test him. Others trash-talk him. Many tap out on him. He doesn't seem to notice. He says nothing. He shows nothing. He allows nothing.

Welcome to the Island of Kawhi.

*****

Two hours before tip-off at AmericanAirlines Arena, and the Heat have overhauled their game plan. Normally small forward Luol Deng is a vital member of the Miami offense, and coaches deploy a package of plays to free him for shots. But with the Spurs in town and Leonard expected to open on Deng, the Heat decide to shelve most of those plays. To avoid Leonard, they plan on featuring Dwyane Wade in the first quarter, knowing full well that Popovich will eventually switch Leonard onto Wade and force another adjustment. No defender in the league, Miami coaches acknowledge, prompts anywhere near as many machinations as Leonard. "You go AmericanAirlines Arena, and the Heat have overhauled their game plan. Normally small forward Luol Deng is a vital member of the Miami offense, and coaches deploy a package of plays to free him for shots. But with the Spurs in town and Leonard expected to open on Deng, the Heat decide to shelve most of those plays. To avoid Leonard, they plan on featuring Dwyane Wade in the first quarter, knowing full well that Popovich will eventually switch Leonard onto Wade and force another adjustment. No defender in the league, Miami coaches acknowledge, prompts anywhere near as many machinations as Leonard. "You go at him," one coach says, "you're asking for trouble."

When Leonard arrived in San Antonio almost five years ago, the Spurs did not know much about him personally. Even scouts, who conduct famously comprehensive background checks, found him difficult to pin down. They were aware he was a physical marvel, 6'7" with a 7'3" wingspan and 11-inch hands, too strong to screen and too long to elude. He was a worker who took his own lamps to 6:30 a.m. sessions at San Diego State's Viejas Arena, when the lights were off. He lost his dad at 16—Mark Leonard was shot and killed at the car wash he owned in Compton—but Kawhi's self-effacing manner goes back much further. He never even liked celebrating his birthday. In San Antonio he opted to live with his mom, his bedroom upstairs and hers down. They played Jenga at night over enchiladas.

"You have to be the best defender in the league," Popovich told Leonard. "You have to be Bruce Bowen times 10." Some first-round divas might have bristled, getting compared to an undrafted grinder like Bowen, but not Leonard. "That's how I grew up," he says. "Just play defense—and make a basket." As a kid he played defense in pickup games. He played defense in AAU games. In other words, he played defense when nobody played defense. He could lock up the point guard, the center and all positions in between, then sneak out of the gym before anyone noticed, an ideal day.

Popovich is toughest on his best players, and Leonard is no exception, but the coach softened elements of his delivery for his silent stopper. "When Kawhi makes a mistake, he's almost apologetic," Popovich says. "He doesn't want to disappoint anybody. There are times he does something well, and I have to tell him, 'That was super. That was fantastic. That was a helluva job. You can smile now. You can feel great about yourself.'" Popovich became fluent in Leonard's style of nonverbal communication. "If I bring him out too early, for example, he'll go like this": Popovich curls up one side of his lip. "What he's saying is, 'Pop, why the f--- are you bringing me out so early?' but he'd never actually say that. So I tell him, 'I'll get back to you,' and he nods and sits down."

Popovich informed Leonard that his defense would determine his minutes. Shelton, who also trains professional football players, treated Leonard like a shutdown corner. Shelton made him backpedal through speed ladders, wiggling his hips and cycling his feet, as if shadowing a receiver running post patterns. In his second season, Leonard averaged more than 30 minutes as he began to anticipate sets and diagnose pick-and-rolls. "I look at film," he explains, "but more than watching individual players, I'm trying to watch a team's whole offensive scheme. I'm trying to know their tendencies so I can ... guess. That's what it comes down to, really, making the best guess. I'm trying to change up their scheme."

Just because he isn't yapping doesn't mean he isn't thinking. His guesses, as he calls them, are the product of keen observation and careful decision making. "He's not Allen Iverson, wild and bizarrelike, getting steals because he's in passing lanes," Popovich says. "This guy guards you. People do not like playing against him." It is an uncomfortable experience, getting stalked for four quarters by a wide-eyed stoic who betrays no fatigue or feeling. "There are times you think you've got him beat," says Spurs assistant coach Chad Forcier. That's when one of Leonard's boa constrictor arms drops out of the rafters and strips you clean.

The Spurs notice how his marks react to him. They wince when he checks in. They hot-potato the ball. They never post him up and rarely iso. "More than his length, his strength, his quickness, that mother------ is so ... locked ... in," says Clippers guard J.J. Redick. "I have no idea what scouting report they give him, but he knows every play, and he takes no breaks. I'm still going to run my stuff. I'm going to be aggressive. I'm going to work for my shot. But I have to recognize he's probably not going to make any mistakes, and I may only get a shot or two in a quarter. I have to be O.K. with that. I have to be O.K. knowing there will be more space for somebody else."

The Pacers' Paul George tried to force jumpers against Leonard in a game this season and went 1 for 14. The Knicks' Anthony went 4 for 17. The Thunder's Kevin Durant went 6 for 19. On Jan. 22, the 10th anniversary of Kobe Bryant's 81-point outbreak against the Raptors, the Lakers faced the Spurs at Staples Center. Matched with Leonard, Bryant marooned himself in the corner, finishing with five points on nine shots. "I'm not going after him anymore," Bryant said with a smile.

Bryant's approach is the most prudent. According to NBA.com's stats team, players guarded by Leonard shot 39.8% in the first half of this season, 4.5% lower than their normal rate. But those numbers don't illustrate the extent to which he has spooked the league. NBA.com also keeps track of "prevent defense," quantifying how much defenders depress the touches, points and field goals of players they are guarding. Leonard ranks among the top 10 in all three categories among perimeter players. "Teams look at that," an Eastern Conference scout says, "and go in another direction." Leonard is to the NBA what Deion Sanders, and more recently Darrelle Revis, have been to the NFL. Revis Island, the nickname that refers to the side of the field where receivers are stranded every Sunday, has made its proprietor very rich. Leonard could have stayed on his island forever. He could have been Bruce Bowen times 20. He could have reaped all the minutes with none of the exposure. Just play defense—and make a basket.

Looking back, he curls his lip. He wanted more.

*****

Kawhi Leonard spent all day in the bleachers at Attack Athletics Gym in Chicago. It was the 2011 NBA draft combine, and Leonard was there to be measured and prodded, but like most top prospects, he was advised to skip the drills and competitions. At some point he grew weary of watching. He strode onto the court, grabbed a ball and started shooting. He couldn't help himself. After 10 minutes he was shooed away.

Chip Engelland saw those 10 minutes. Good base, thought Engelland, a Spurs development coach and one of the most respected shot doctors in the world. Good form. It was a surprising rave to give a brick mason who shot 25% from three-point range in two college seasons.

Many in the San Antonio front office were hesitant when they sent point guard George Hill to Indiana for Leonard on draft night. "We were all looking at each other like, Are we really going to do this?" Popovich remembers. "We were scared s---less. We don't know this kid. He's not a shooter. He's not a scorer. He's not a perimeter player. He's a big guy who can rebound."

Engelland cast a vote of confidence based largely on the 10-minute session in Chicago that was not supposed to have happened. He lowered Leonard's release, which was over his head, and made him study photos of Bryant's form. He predicted that Leonard would someday qualify for the three-point contest.

Shortly after the Spurs returned from the lockout and Leonard reported to an abbreviated training camp, Engelland approached him. "Do you want to be great?" Engelland asked. Leonard, as is his custom, did not immediately reply. "It isn't an easy question," Engelland said. "Good is fine. Good is good. Sleep on it."

The next day, at practice, Leonard wandered over to Engelland. "I do," he said. "I want to be great."

So began an ambitious enterprise that unfolded almost entirely behind the scenes, as Leonard liked it. Anybody who watched the Spurs on TV saw Leonard defending, rebounding and occasionally firing up a prayer from the corner. The coaches seemed to be turning him into a three-and-D specialist. In fact, they were growing him into the NBA's next two-way dynamo.

Every morning all the Spurs are instructed to take a vitamin. "You have your toast, your eggs and your Flintstone chewable multi," says Forcier. Except this vitamin refers only to the skills an individual player is trying to polish. Maybe your vitamin includes free throws or corner threes or pull-ups or jump hooks or turnarounds. Leonard's was the biggest Barney Rubble pill ever ingested; it contained all those ingredients and more. "There's so much he can do," Engelland says, "so there was so much we put in his vitamin."

They started with the corner threes, but they also looked ahead, to a time when his jump shot would be so true that no defender would dare leave him. So they honed the one-dribble pull-up, the Kobe step-through, the fallaway, the shots headliners take. At the 2013 All-Star Game, Leonard sat with Bryant in a Nike suite, deconstructing moves. "He didn't say much," Bryant remembers, "but he asked very pointed questions." Leonard yearned to display his expanding arsenal, but Popovich kept him largely under wraps. The Spurs were playing a long game.

When San Antonio took the championship in '14, Leonard withdrew from consideration for Team USA, supposedly exhausted after a second straight Finals run. He retreated to San Diego for an entire summer of three-a-day workouts, some sessions so grueling that he would drop a dozen pounds in a 24-hour span. He lifted NFL-caliber weight, leg-pressing more than 600 pounds and squatting more than 400. When the Spurs sent him the Larry O'Brien Trophy so he could parade it around La Jolla, he let the hardware sit in his apartment lest his training schedule be disturbed. "He's pretty much a machine," Shelton says, though Leonard does have his limits. He refuses the cherry beet juice trainers foist on him to assist recovery.

While most Spurs are told what to put in their vitamin, the coaches let Leonard decide for himself, a way to foster conversation. "You never know what it's going to be," Forcier says. "Sometimes it's just shoot free throws and talk about life." Leonard likes modern architecture and is building a house in San Antonio. His girlfriend is his college sweetheart, Kishele Shipley, and his closest buddy is his high school guard, Jeremy Castleberry, now a member of the Spurs' video department. Leonard is wary of new people and things. He wears a hat emblazoned with MORENO VALLEY and sniffs when asked if he is from Riverside, a larger city 12 miles away.

The Spurs unveiled their grand experiment in stages, finally unleashing the full Kawhi last season. Popovich transferred to Leonard plays that had been reserved for veteran wing Manu Ginóbili. He let him run after rebounds like the Warriors' Draymond Green. He created small forward post-ups for the first time. In February, when the Spurs and Magic were tied with 13 seconds left, Popovich drew up a play in a timeout. Then he erased it and scribbled an iso for Leonard instead. Leonard pulled up from 19 feet and drilled the game-winner. His celebration was characteristically muted. No need to make a scene.

Just as Engelland forecast, Leonard earned an invitation to the three-point contest at All-Star weekend, last month, though he turned it down. The only event he attended was Sunday's game, in which he started for the Western Conference. "We got the win," he declared afterward, perhaps the only person who cared—and certainly the only one who defended.

"I try to keep things light with him," Popovich says, "but I also let him know it is now his responsibility to bring it night after night like Kobe, like Michael, like Magic, like Larry, like Tim Duncan. He is in that category." Popovich shows Leonard video of Charles Barkley—to see how the Chuckster manipulated double teams—and urges him to befriend Bryant. With all due respect to Bruce Bowen, the stakes have risen.

"To be a true scorer, like Kobe or Michael or LeBron, I think you have to be a little selfish," says Sean Elliott, the former Spurs star who is now their TV analyst. "You have to be a little cocky." Elliott considers the postgame interviews he conducts with Leonard, the pains he takes to avoid yes-or-no questions, for fear of one-word answers. "I don't know if there's ever really been a superstar like this."

*****

The man behind the basket at Staples Center wears a pink ski hat and pink pants. In one hand he carries a baby in a Spurs onesie and in the other a silver sign thanking TIMMY D. "Timmy!" he shouts. "TimmyTimmyTimmy!" The chorus continues until Duncan pauses his pregame warmup, offering a dutiful smile and an awkward wave. Yes, it is possible to chase greatness without stardom, and here is living proof. "Kawhi Leonard," says San Antonio forward David West, "is Tim Duncan 2.0." It's a good line, but an oversimplification. Though both are allergic to attention, Duncan can be assertive and outspoken, just not at press conferences. He is a carnival barker compared to Leonard. The Spurs attempt to unlock their earnest leader with humor. Leonard laughs when Popovich trips over the edge of the court or when head trainer Will Sevening tells his customary joke on the team bus after road wins. Leonard dissects matchups with veteran Rasual Butler, and he recently crossed the dining room at Prime 112 in Miami to introduce himself to Terry Bradshaw. "Confidence," Duncan says, "is all that's left."

Leonard may never put up 50 points and produce six Vines, but how about 25 points, eight rebounds and 32 minutes of stick-'em defense, strung together for a month, for a season, for multiple seasons? "Then you're great," Engelland says. "He's not looking to be great for a night. He's looking to be great for a long time." Those who know Leonard best believe he keeps mental checklists of opponents he hopes to vanquish and honors he aims to collect.

He is currently averaging 20.8 points and 6.9 rebounds, and in the Season of Steph, that won't fetch him any more than a runner-up finish for MVP. San Antonio (53–9), with the best point differential ever and the best D in a decade, may also be playing for second. It is such a bizarre year, because as historically dominant as the Spurs have been, there are so many shooters at Golden State and only one Kawhi Leonard in San Antonio. When the juggernauts collided on Jan. 25 in Oakland, the Warriors singed the Spurs, Leonard included, in a 120–90 win.

But San Antonio remains the most plausible threat to the Dubs' destiny because of Leonard, whose massive hands have turned the crank on a championship window that was supposedly closing a decade ago. "He changed the course of our organization," says Spurs general manager R.C. Buford. "He gave us a second wind. He was the breeze in our sails." When Duncan, Ginóbili and Tony Parker were in their prime, San Antonio could persist with specialists such as Robert Horry, Brent Barry, Michael Finley and Bowen. As the core players aged, they needed somebody to absorb more of their minutes and duties, and Leonard entered just in time. He allowed Popovich to preserve the standbys. Buford wonders whether Duncan and Ginóbili would still be playing without Leonard. His island has become theirs.

Kawhi, according to his mother, was the name of an African prince. Kauai is more difficult to define. But Polynesian historians suggest a translation befitting a young man who has draped himself over the NBA, reviving one franchise and suffocating many others:

A favorite place around the neck.