BELO HORIZONTE, Brazil >> The fireworks began at dawn. All around this city, loud pops and bangs rang out as men and women and children, so many dressed in yellow, set off flares and beeped car horns. It was supposed to be a magical day. The Brazilian national soccer team, playing at home, was one game away from a World Cup final.

No one could have guessed the tears would come before halftime. No one could have imagined there would be flags burning in the streets before dinner. Certainly no one could have envisioned that Brazilian fans, watching their team play a semifinal in a celebrated stadium, would ever consider leaving long before full time.

It all happened. The 2014 World Cup, first plagued by questions about funding and protests and infrastructure and construction, then buoyed by scads of goals and dramatic finishes and a contagious spirit of joy from the locals, will ultimately be remembered for this: the home team, regarded as the sport’s superpower, being throttled like an overmatched junior varsity squad who somehow stumbled into the wrong game.

The final score was Germany 7, Brazil 1. It felt like Germany 70, Brazil 1. By the end, the Germans were barely celebrating their goals anymore, and the Brazilians, starting with their coach, Luiz Felipe Scolari, could manage little more than blank stares. In the stands, the Brazilian fans — the ones who stayed around at least — passed the time by cycling through obscene chants about each player, as well as the Brazilian president, Dilma Rousseff.

"I think," Scolari said afterward, "that it was the worst day of my life."

He was surely not alone in that sentiment. Sports are often a haven of hyperbole, but there was little risk of that here on Tuesday. Given the circumstances and the stakes, this result — a soccer massacre of the highest order — might well be remembered as the most surprising in World Cup history.

It was also Brazil’s first loss in a competitive home game since 1975, a stretch of more than 14,000 days.

"It was the biggest embarrassment of all World Cups — 7-1 in a semifinal playing at home?" said Marcel Guimarces, 38, who traveled to Belo Horizonte from Brasmlia. "Not even in a video game."

The aftermath of Brazil’s defeat could turn ugly. There were reports of a mass robbery at a fan party in Rio de Janeiro and of fans burning Brazilian flags in the streets of Sao Paulo even before the match was over. Local organizers and government officials have been concerned for weeks about the possibility that demonstrations — which have, for the most part, been subdued — would become more intense if Brazil were to be eliminated.

Many Brazilians have been upset about billions of dollars spent on new stadiums and other World Cup-related projects. The success of the national team provided a natural balm, but now those emotions may become more inflamed.

"The time of bread and circus is over," said Lisa Rodrigues da Cunha Saud, who attended the game with her brother. "Instead of stadiums, we need hospitals and schools," she added.

Brazil played this match without its top scorer, Neymar, who was injured in the quarterfinals, as well as without its top defender, captain Thiago Silva, who was suspended. As important as both players were to Brazil, however, it is difficult to imagine either one having made much of a difference.

The Germans played with grace and unity and raw power. Thomas Mueller opened the scoring in the 11th minute, blasting home a corner kick from just six yards out. Miroslav Klose followed about 12 minutes later, knocking in a rebound to record his 16th career World Cup goal and become the tournament’s all-time leading scorer.

By then, the mood at the Estadio Mineirao had already deflated, but the fans had no idea what was yet to come. In the next six minutes, Germany scored three more goals, which essentially ended the match before a half-hour had been played. Toni Kroos scored two of those goals; Sami Khedira added the other.

"I couldn’t change anything," Scolari said. "It was one goal after the other. There was nothing to be done during that breakdown."

The second half was more of the same. Andri Schuerrle scored two more goals for Germany. Brazil kicked the ball around as if in a stupor.

In the end, Tuesday’s sunrise fireworks seemed far away. They had been a rousing beginning, a joyous start to a day Brazilians hoped they would always remember. Then came a German juggernaut, and when it was over, all that was left was a game that a nation of soccer fans can only hope to forget.

Germany 7, Brazil 1

First half–1, Germany, Thomas Mueller 5, 11th minute. 2, Germany, Miroslav Klose 2, 23rd. 3, Germany, Toni Kroos 1, 24th. 4, Germany, Toni Kroos 2, 26th. 5, Germany, Sami Khedira 1, 29th.

Second half–6, Germany, Andre Schuerrle 2, 69th. 7, Germany, Andre Schuerrle 3, 79th. 8, Brazil, Oscar 2, 90th.

Shots–Brazil 18, Germany 14.

Shots On Goal–Brazil 13, Germany 12.

Yellow Card–Brazil, Dante, 68th.

Offsides–Brazil 3, Germany 0.

Fouls Committed–Brazil 11, Germany 14.

Fouls Against–Brazil 14, Germany 10.

Corner Kicks–Brazil 7, Germany 5.

Referee–Marco Rodriguez, Mexico. Linesmen–Marvin Torrentera Rivera, Mexico; Marcos Quintero Huitron, Mexico.

A–58,141.

Sam Borden, New York Times

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