Rio de Janeiro

The first signal that this was going to be a transformative World Cup arrived on the second day of the tournament. That’s when Holland’s Robin van Persie caught up with a masterful 51-yard bomb of a pass from the midfield, then nailed a diving header into Spain’s goal, part of a 5-1 thrashing of the defending world champions.

The next day, giant-killer Costa Rica swarmed a defensive Uruguayan team with three second-half goals, punishing the 2010 semifinalists for their passivity. Two days later, U.S. captain Clint Dempsey scored just 29 seconds into the game, his ears still buzzing with the parting words of coach Jurgen Klinsmann just before kickoff: “Attack!”

This week brought the ultimate onslaught—Germany’s merciless, 7-1 thrashing of host Brazil, which brought the whole concept of the “attack” to an entirely new level.

After years of timid, low-scoring play, that one word has become the theme of Brazil’s World Cup. When the history of this tournament is written, the sport’s cognoscenti will likely point to it as an event that changed the game. The finalists, Germany and Argentina, have survived the most offense-oriented tournament of the modern era, a series of games where playing defensively almost guaranteed an early exit.

“There is no clear defensive strategy anymore,” said France coach Didier Deschamps, whose young, lightning-fast team romped through its group, scoring eight goals in its first two games. “I remember a few years ago, there were some very boring World Cup matches. Not this year. Now it’s end-to-end soccer, it goes from one box to the other, and it’s really entertaining,” he said.

Even Argentina’s triumph Wednesday over the Netherlands, a scoreless draw decided on penalties, featured a series of onslaughts that perfectly organized defenses thwarted before they turned dangerous. Collectively, the players covered some 275,000 meters up and down the field during the 120-minute marathon, or roughly 172 miles.

“There are players who are sore, beaten and tired,” Argentina coach Alejandro Sabella said after the match. “It is the result of a war.”

The attacking style also helped the sport earn its first full-throated embrace from the American sporting public. Pundits have been debating for weeks whether soccer has finally reached a watershed moment with U.S. audiences. All those decades of mop-haired American kids swarming after the ball in their local leagues were finally bearing fruit. TV ratings soared, up 43% since 2010. Wednesday’s semifinal scored a 4.3 in overnight ratings compared with 2.8 four years ago.

Skeptics argued that these games were a fluke, that Americans artificially benefited from an ideal time zone; Team USA made it to the final 16; the NFL, NBA, MLB and Nascar have little to fear.

Even if it turns out that Americans still haven’t caught up with the rest of the world, here is what the past six weeks have proved: Soccer is catching up with America. The games were fast, furious and physical, ideal for the razzle-dazzle of TV and the Web—just what Americans have always loved in their sports.

Fans abroad, too, had been frustrated with so many matches with so little scoring, with players moving the ball up the field at a slow jog, tapping measured passes to their teammates, collapsing to the ground in full writhe.

A team that dared to play passively for even the briefest period of a match was guaranteed to hear derisive howls from the Brazilian crowds, no matter how hot and humid it was or how tactically intelligent slowing down the game might have proven.

“Every team has realized you need a balance, that you need to attack and defend,” said Avram Grant, the former manager of the English club Chelsea. “If all you do is defend, you lose.”

The most basic measure of aggressiveness is the number of goals scored in the group stage of the tournament, before teams inevitably tighten up in knockout games where a single goal usually spells doom. (Of course, anyone who watched Belgium’s 38-shot bombardment of the U.S. or the Netherlands’ 20-shot assault on Costa Rica wouldn’t call those matches passive, despite the limited scoring). This World Cup produced a stunning 2.83 goals a game in the group stage, a 35% increase over 2010. Since then, the overall scoring average is 2.7, compared with the snooze-worthy 2.27 goals four years ago.

Even if it turns out that Americans still haven’t caught up with the rest of the world, here is what the past six weeks have proved: Soccer is catching up with America. The games were fast, furious and physical, ideal for the razzle-dazzle of TV and the Web—just what Americans have always loved in their sports.

Fans abroad, too, had been frustrated with so many matches with so little scoring, with players moving the ball up the field at a slow jog, tapping measured passes to their teammates, collapsing to the ground in full writhe.

A team that dared to play passively for even the briefest period of a match was guaranteed to hear derisive howls from the Brazilian crowds, no matter how hot and humid it was or how tactically intelligent slowing down the game might have proven.

“Every team has realized you need a balance, that you need to attack and defend,” said Avram Grant, the former manager of the English club Chelsea. “If all you do is defend, you lose.”

The most basic measure of aggressiveness is the number of goals scored in the group stage of the tournament, before teams inevitably tighten up in knockout games where a single goal usually spells doom. (Of course, anyone who watched Belgium’s 38-shot bombardment of the U.S. or the Netherlands’ 20-shot assault on Costa Rica wouldn’t call those matches passive, despite the limited scoring). This World Cup produced a stunning 2.83 goals a game in the group stage, a 35% increase over 2010. Since then, the overall scoring average is 2.7, compared with the snooze-worthy 2.27 goals four years ago.

Germany’s forward Miroslav Klose, left, scored against Brazil Tuesday. Agence France-Presse/Getty Images

There are other, more subtle numbers that show how much more open and attack-minded this World Cup has been than previous tournaments, especially the one played just four years ago, highlighting how quickly the game at its highest level transformed.

For instance, teams stopped getting bogged down in their own half of the field as often. Through the semifinals, the number of unsuccessful passes in the defensive half had dropped to 28.9 a game from 32.2. And when they got across midfield, they were increasingly attacking as fast as they could in the open spaces on the wings. Long-range passes from the flanks, known as “open-play crosses,” are becoming more popular compared with the more conservative touches through the middle of the defense, known as “through balls.” The ratio of through balls to crosses fell to one through ball for every 15 crosses this year, compared with one for every 14 in 2010. Overall, the number of through balls a game has dropped to 1.8 compared with 2.28 in 2010.

Karim Benzema of France celebrated scoring the first goal against Honduras with Patrice Evra, Mathieu Valbuena and Antoine Griezmann June 15. Getty Images

“The modern game is bigger, faster, and stronger,” said Marcelo Balboa, who anchored the U.S. defense in the 1990s. “When I played, teams would sort of slow down to let their playmaker catch up. You sure don’t see that anymore.”

How this World Cup became so much more physical, and so much faster and attack-minded than any in recent memory is a result of several shifts in the game, some of which occurred across the past two decades, while others occurred just in the last four years.

The biggest change leading to the shift in style is the quality of the athlete that is stepping on the field, said Roberto Martinez, the Spaniard who coaches Everton and analyzes games for ESPN.

“Twenty years ago the physical condition wasn’t comparable to what you see today.,” he said. “There is more focus on ball skills, but we have also tacked on speed and strength. You have real athletes playing this game now, and they’ve made it faster and more physical. You have so much more pace and power on the ball and that lets you attack.”

Case in point, James Rodríguez of Colombia, the 22-year-old striker blessed with speed, size and brilliant touch. He scored a tournament-leading six goals in five matches.

Balboa, who is 6-feet tall and thick, said he and his partner in central defense, Alexi Lalas, who is a broad-shouldered 6-foot-3, felt like giants on the field in 1994. Now they would be merely average.

Yet it’s how those athletes have been playing once they take the field that has made for the most dramatic changes. Throughout the 1990s, and into the early 21st century, the most successful teams were the ones who had the best playmakers and center forwards in the middle of the field, players like Romario and Bebeto for Brazil, or France’s Zinedine Zidane. These were the field generals, and their teams rarely attacked without them running the show, even if that meant waiting for them to catch up.

However, these teams could be beaten by an opponent that clumped its defenders in the middle, like Italy, the 2006 world champions, whose “Catenaccio”—literally, “door bolt”—aimed to cut down any team that tried to find an offensive flow in the heart of the field.

With so little space left in the middle, the stars that teams normally relied on to lead the attack began drifting to the wings. That’s where they could find space. It’s also where the most potent attack is an irresistible product of speed, long-range passes from the midfield, and lightning-quick crosses into the penalty area. Twenty years ago, it’s likely that Cristiano Ronaldo, would have been leading a centralized attack. Today Ronaldo, like the Netherlands’ Arjen Robben, or Brazil’s Neymar, or Germany’s Thomas Müller or Colombia’s Rodríguez, may start in the center of the field, but heat maps produced through video tracking show they spend most of the matches searching for openings on the left or the right. Among the semifinalists, only Argentina’s otherworldly forward Lionel Messi does most of his handiwork in the middle of the field.

Patrice Evra, left, of France with Thomas Mueller of Germany July 4 Popperfoto/Getty Images

“The best teams now, they have a couple of skilled guys in the middle, but their fastest and most creative players are on the outside,” Balboa said. “And that’s tough to keep up with when the play is moving so fast.”

That has been especially true in the heat and humidity of Brazil, where players ran out of gas quickly and so many of the defenses became stretched. This led to yawning gaps in the field, wide open for the taking.

“This game is ultimately all about space, creating it, finding it, exploiting it, limiting it,” said Lalas, another ESPN analyst. “Where are you going to find the space most often? On the outside. And when you get the ball you go.”

Finally, every World Cup is in part a reaction to the last one. Since 2008, the great obsession in international soccer has been trying to figure out how to stop Spain, the world champions in 2010 and European champions in 2008 and 2012. Along with the club team Barcelona, Spain changed the way soccer is played by developing a group of players whose ability to make quick, short passes was so superior that it became almost impossible for even the best teams to get the ball from them.

Sitting back and waiting for the Spanish to commit a turnover or to produce an ill-fated attack became an exercise in total frustration, since the team would eventually find a seam and pick an opponent apart. The Spanish won their last four games at the 2010 World Cup by getting a single goal—then playing keep-away. Regardless of the score, none of the games were particularly close.

At first, many skilled teams emulated parts of that possession-heavy style. Then came the counter-reaction. They decided they had only one choice: When the other team has the ball, push up and attack the ball with abandon, and when you have the ball, attack the goal as fast as you can.

That concept is at the heart of the modern German soccer machine, the heavy favorite after the clinical destruction of Brazil in the semifinal. Not only are the Germans nearly the equal of Spain when it comes to holding the ball, they defend so aggressively and attack so often that the constant assault is the team’s greatest defensive weapon.

No matter the score, Sunday’s final game is likely to produce a thrilling, back-and-forth final between Germany and Argentina. After its historic win against Brazil, Germany wouldn’t dare play any other way. Led by Messi, who countryman Diego Maradona once described as having jet engines in his legs, Argentina gets the ball to its No. 10 and goes forward every chance it gets. Nothing puts an opposing defense on its heels like Messi with the ball in space, zooming toward the goal.

“We’re in a moment where everyone is working out how to play attacking and dynamic soccer,” Martinez said. “There have been times when this game has been about defense, but right now it’s all about offense.”