The outcome of the NBA Finals will be decided by one thing: Whether Miami's fortresslike defense can withstand repeated assaults from the Mavericks' Dirk Nowitzki

The scene at American Airlines Center on Sunday morning could have taken place in any driveway from Würzburg to Fort Worth. Corey Brewer, a reserve forward for the Mavericks, was the last player at shootaround, dribbling 40 feet from the basket, leaping off his left foot, limbs flailing as he let fly. "Like Dirk Nowitzki!" he yelped, and then grimaced as his skyscraping three-pointer smacked off the side of the rim.

Nowitzki's moves are inimitable: the methodical spins and turnarounds, the lumbering leaners and fadeaways, the surprising up-and-unders and reverse layups. Since he is seven feet and cannot run like Dwyane Wade or levitate like LeBron James, his moves may appear cumbersome. But he has so many of them, employed from such diverse angles and locations, that he has earned the title granted only a few one-on-one dynamos: unguardable.

In this era of zone defenses, early double teams and advanced analytics, when coaches know what percentage a player shoots while moving to his left after setting the screen on a pick-and-roll, there would seem to be an answer for everybody. But Nowitzki has led his team to the Finals with one of the most awesome individual surges in postseason history. "Right now no defense can determine whether he makes or misses," says Dallas backup center Brendan Haywood. "It's up to him."

That was certainly true against the Lakers and the Thunder, but the Heat has been as tightfisted as the Bulls and the Celtics this season, which may come as a surprise to those who assume James and Wade subsist on alley-oops alone. Miami actually prevents as many highlights as it produces. Coach Erik Spoelstra employed a lesser-known Big Three—6'8" Udonis Haslem, 6'9" Joel Anthony and 6'11" Chris Bosh—to cover Nowitzki like an extra jersey in the finals. While Nowitzki provides Heat defenders with their most dynamic challenge, they do the same for him. In the end Haywood may be right that Miami's coverage cannot determine the result of a Nowitzki jumper, but its defense will very likely determine the winner of the championship.

With the series tied and less than five minutes remaining in Sunday's Game 3, Haslem sat at the end of the bench, sipping a cup of water. This was the moment he had longed for when he rushed through six months of rehabilitation this season on his surgically repaired left foot. Now that his opportunity had finally arrived, Haslem, who had played nearly 26 minutes in the game to that point, felt too lightheaded and leg-weary to take advantage. He had asked Spoelstra to give him a minute. Spoelstra gave him 83 seconds. Then he sent Haslem back on the floor, dehydrated but determined, with Nowitzki in the middle of another Larry Bird impersonation.

In Game 2, Nowitzki scored the last nine points for Dallas, including a driving layup on Bosh to cap an unimaginable comeback that saw the Mavs rally from 88--73 down with 7:14 left to win 95--93. Why Spoelstra chose Bosh over Haslem, who smothered Nowitzki in the 2006 Finals, was a question even the coach could not answer. Nowitzki shot 60% against Bosh in single-coverage situations in the first two games of the series, according to Synergy Sports, and only 38.5% against Haslem. In Game 3, with Nowitzki rolling again, Spoelstra had to try a new stopper. It was Nowitzki versus Haslem, just like '06, blond curls versus braids. Nowitzki had scored 12 straight points before Haslem baited him into an errant pass in the final minute. With 4.4 seconds left and the Mavericks trailing 88--86, Nowitzki caught an inbounds pass at the top of the arc, took two dribbles to the right of the free throw line, spun back toward the middle, pump-faked once and planted his left foot. Haslem, having studied Nowitzki's pump-fake on video, didn't flinch. He raised his arms and pressed his chest into Nowitzki's right shoulder. As Nowitzki elevated and released, Haslem held his breath and told himself: "It's an awkward shot, but awkward shots for everybody else are good shots for him." As the ball kicked off the back rim, Haslem exhaled, stalked to center court and threw a combination of punches at the air.

Nowitzki walked off with 34 points, facing a 2--1 series deficit. "Derrick Rose was unguardable all season," Nowitzki had said the day before, on the way from his English press briefing to his German press briefing. "Miami took away his efficiency in the playoffs. They are swarming me too." Nowitzki averaged 28.3 points through the first three Finals games despite a torn tendon in his left middle finger, suffered in the fourth quarter of Game 1. But he required an average of 20.3 shots and coughed up 10 turnovers, many of which resulted in aerial gymnastics on the other end. As Nowitzki watched the Heat tear downcourt repeatedly—two dribbles and a dunk—he fiddled with the hard splint over his finger. The unguardable man had met the impenetrable D.

Pat Riley coached the Knicks in the early 1990s, when they trapped ball handlers on almost every pick-and-roll, leaving screeners on the perimeter and daring them to fire. Riley came to Miami in '95 and altered his philosophy slightly soon thereafter. Instead of consistently trapping the pick-and-roll, Heat defenders showed hard but scrambled back to the screeners. "He changed because he saw all these big guys coming into the league who could shoot," says Jeff Van Gundy, who worked as an assistant coach for Riley with the Knicks, and is now an ESPN analyst. "One of those guys was Dirk Nowitzki."

No one spent more time studying Riley's new defense than Spoelstra, who was hired as the Heat's video coordinator in '95 and given a windowless office known as the Dungeon at old Miami Arena. When the team played on the West Coast, Spoelstra stayed in the Dungeon until 1 a.m. watching the game, then edited the tape until dawn and drove it to Miami International Airport in time for the first flight out. He used Delta Airlines's Dash service, which delivered the tape to the team on the same day.

"Erik lived in Miami but never saw the sun," says Chris Wallace, a former Heat executive who is now the Grizzlies' general manager. "He was learning Pat Riley's system. There was no doubt he would be defensive-oriented." Last season, Spoelstra's second as the Heat's coach, the team ranked second in the NBA in opposing field goal percentage and points allowed. With a front line featuring the ineffectual duo of Jermaine O'Neal and Michael Beasley, Miami won 47 games and thus remained a relevant free-agent destination.

After landing its vaunted trio last July, the Heat was prematurely billed as the ultimate AAU team, stacked with flashy scorers who would surely care more about reverse jams than hard shows. In another organization, with another coach, the season might have devolved into a string of exhibitions. "But when you come here, you know it's going to be defense first," says former Miami point guard Tim Hardaway. "That's the culture Pat Riley created. It's the Heat Way."

James and Bosh could not fully understand what they signed up for until they reported to Eglin Air Force Base outside of Fort Walton Beach, Fla., for training camp, and Spoelstra didn't mention anything about offense. He assumed, correctly, that the Heat would generate plenty of points off stops and turnovers. In scrimmages Spoelstra pitted James against Wade, Bosh against Haslem. "The competition was fierce," Haslem recalls. "At camp you usually give up layups on the fast break because you don't want anybody to get hurt. We were contesting everything."

Spoelstra had to meld three megastars with 12 spare parts, and defense was the catalyst he used. Because the system relies so heavily on rotations, players had to develop faith in one another quickly. "If we're on Dirk Nowitzki and have to rotate, we have to trust guys to be there," says Bosh. Spoelstra did not even implement Miami's current offense until January and did not install its full fourth-quarter package until March.

The Heat faced many early obstacles—in crunch time, James and Wade would stand on opposite sides of the court so as not to step on each other's Nikes—but defense was never an issue. Spoelstra explained that NBA history is filled with headliners who won championships because they used their athleticism to do more than score. He rarely talked to the team about their offensive percentages, harping on defensive rankings. James and Bosh both became better defenders, surrendering lower field goal percentages and points per possession than they did last season with the Cavaliers and the Raptors, respectively, according to Synergy. "Obviously we have offensive firepower and talent that can take over at certain moments," Wade says. "But it's our engine, our effort, that's gotten us to this point and that, no matter what, we could fall back on."

The Heat loads up on the strong side, and against most teams, the players are fast enough to recover and rangy enough to contest when the ball gets swung to the weak side. But there were two opponents that worried Miami coaches all the way back in camp, because of both the speed with which they shuttle the ball around the perimeter and the accuracy of their three-point shooters. One, predictably, was the Celtics. The other was the Mavericks.

They landed in Miami at 7:30 p.m. on the Sunday before the series began, and while most of the Mavs went out to dinner, Nowitzki checked into his hotel room and immediately caught a ride to American Airlines Arena. (Yes, American Airlines is the winner in this series either way.) A lot of players like to take extra shooting practice during the Finals, but it is part of Nowitzki's routine throughout the season. "We are always waiting on him for dinner," says reserve forward Brian Cardinal. Even at home, Nowitzki will go through a regular afternoon workout with the team and then return at night to shoot alone.

Nowitzki is scoring 28.4 points per game in the playoffs on 50.6% shooting, 52.5% three-point shooting and 93.9% free throw shooting. He has always been underrated in the postseason, averaging 26 points and 10.4 rebounds for his career, and he attributes this year's spike only to experience and an improved supporting cast. His repertoire is constantly being expanded and honed in those after-hours workouts.

While Nowitzki tried to acclimate himself to the arena, the Heat probed for ways to make him uncomfortable. The plan was to deny him the ball to the three-point line, treating the perimeter like the post. By overplaying Nowitzki, Miami encouraged him to drive. Nowitzki has improved his ballhandling in recent years, but the Heat allowed the lowest shooting percentage at the rim this season of any team, with Wade, Anthony and James each ranking among the top shot blockers at his position. They preferred to see Nowitzki drive the lane rather than pull up on the perimeter.

Most stars have one or two sweet spots, places on the floor where they like to shoot. Nowitzki has at least four, and none are near the rim: both elbows and both "Malone areas," the spaces next to the key where Karl Malone used to camp out. The Heat forced Nowitzki to the baseline and trapped him with a second defender from the low block, a strategy the Spurs made popular. By pinning Nowitzki on the baseline, teams are able to shut down his passing lanes and limit his playmaking ability, though they also risk giving him shots to the left of the basket, yet another semi-sweet spot. The Heat prepared for Nowitzki with such fervor that Spoelstra had to cut short practice the day before the Finals because he was worried that his players might hurt each other.

Miami varied its double teams on Nowitzki, often helping Bosh with an extra defender but leaving Haslem and Anthony to fend for themselves. Late in the fourth quarter of Game 2, Spoelstra used Bosh but called off the double, weary of watching Nowitzki find open snipers. The Heat's 15-point lead had vanished. With 10 seconds remaining, Nowitzki made a rip move on Bosh from the foul line, and still the Heat did not double him. The Mavs could not believe what they were seeing. "You can't play Dirk Nowitzki one-on-one with a game on the line," says shooting guard DeShawn Stevenson. "You just can't."

To that point, the Heat was stifling Nowitzki in post-up situations (where his shooting percentage was down more than 25 points from his regular-season average, according to Synergy) and isolations (where his shooting percentage was down more than 16 points). The Heat had a foul to give, and Nowitzki was convinced that Bosh would use it. Bosh was convinced that Nowitzki would wait a few more seconds to initiate action. Bosh expected Nowitzki to launch his signature fadeaway, but as he leaned in to contest, Nowitzki drove past his right flank, and with his bad left hand lofted an arcing layup over Haslem. Miami had Nowitzki where it wanted him, at the rim, and still he prevailed. "They force us to be on point," says James. "It's the best offensive team against the best defensive team."

Seventy-two hours later, in a nearly identical situation, the Heat used Haslem instead of Bosh, kept Nowitzki outside instead of inside, and wound up winners. That's how slim the margin was in the opening week of the Finals. Two of the first three games were decided by Nowitzki shots in the final four seconds. One went down, one bounced out, and the Heat regained control.

Such is the burden on a star with no formidable sidekick. (Quick: Name the Mavericks' second-best player.) By uniting last summer, Wade and James share the responsibility and the pressure. When teams face the Heat, they have to brace for both of them. When they meet the Mavericks, they can focus on Nowitzki. He is alone in the last-second spotlight, which makes it easier for him to stand out, but also easier to be found.

"RIGHT NOW, NO DEFENSE CAN DETERMINE WHETHER HE MAKES OR MISSES," SAYS HAYWOOD OF NOWITZKI. "IT'S UP TO HIM."

"OBVIOUSLY WE HAVE OFFENSIVE FIREPOWER AND TALENT," SAYS WADE. "BUT IT'S OUR ENGINE, OUR EFFORT, THAT'S GOTTEN US TO THIS POINT."

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Dirk Nowitzki

PICK YOUR POISON

What's the best way to stop Dirk? Who knows? In the first three games of the Finals, Nowitzki has been most efficient when going to the hole: On 25 driving shots (field goal attempts plus shots on which he was fouled), he has scored 35 points. While he generally likes to get a feel for the game from the perimeter (just one foray to the hole in the first quarter), he's lethal down the stretch: His 10 fourth-quarter drives have yielded 18 points. Nowitzki has been almost as tough spotting up: He's averaging better than a point per jumper. He has been least successful in the post, where he's scored only six points on 11 shots. Whatever you do, though, don't foul him: Nowitzki hit his first 24 shots from the stripe.

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HOLE YARDS PAR R1 R2 R3 R4
OUT
HOLE YARDS PAR R1 R2 R3 R4
IN
Eagle (-2)
Birdie (-1)
Bogey (+1)
Double Bogey (+2)