Thomas Müller was the hero on Monday as Germany ran out 4-0 winners against Portugal in Brazil. A team billed as Germany's toughest Group G opponent proved anything but a scare for Joachim Löw's men.

Facing a Portuguese attack spearheaded by Cristiano Ronaldo, Germany went with a more cautious back line that featured four center backs. But the extra safety in defense proved unnecessary for Löw - it was up front where the match was won.

Thomas Müller, the Golden Boot winner at the last World Cup, opened the scoring in the 11th minute with a penalty. After Joao Pereira brought down Mario Götze in the box, the Bayern Munich attacker made it 1-0 with a low shot that keeper Rui Patricio almost stopped.

Germany doubled their lead just after the half-hour mark through Mats Hummels. Toni Kroos' corner into the box found the Borussia Dortmund defender, who headed home to make it 2-0.

Already on the back foot, Portugal's disaster outing became a nightmare just five minutes later when Pepe was sent off. It was unclear whether the red card was for pushing Müller, or the confrontational contact that followed.

Moments before the break, Germany capitalized on their one-man advantage through Müller. Portugal goalkeeper Rui Patricio got a hand on Müller's left-footed strike, but could only manage to slow the ball as it rolled into the net.

Germans secure victory

In a moment illustrative of their overall performance on the day, Portugal's left back Fabio Coentrao was stretchered off in the 65th minute after pulling up with an injury. Germany had an injury scare of their own ten minutes later when Hummels went down with a knee injury. Shkodran Mustafi, a last-minute roster swap for the injured Marco Reus, was brought on to replace him.

While Germany's onslaught was slowed somewhat in the second half, Portugal were unable to truly test goalkeeper Manuel Neuer. Instead, it was the Germans who next found the back of the net. Capping off a brilliant performance, Müller grabbed his third goal of the night in the 78th minute. As Rui Patricio dove to collect an Andre Schürrle cross, Müller poked the ball in from close range to score his eighth World Cup goal in an astonishing seven games.

"Three goals in one match, in the opening match against such an opponent is just great," Müller told German broadcaster ARD. "In the last four years I've had some experience in world soccer and I'm not the kind of guy who gets afraid."

"We got into the match really well and had some half chances then suddenly we were ahead 2-0. In heat like this a lead like that is a great advantage," he added.

The match finished 4-0 to Germany, who, aside from the Hummels injury scare, had reason only to celebrate. The victory blows open a so-called "Group of Death" where Portugal were considered the favorites to advance along with the Germans.

In the second Group G game on Monday, the United States got a late winner to beat Ghana 2-1.