Thomas Muller once again made the difference as Germany qualified as winners of Group G with victory over the United States, who also reached the last 16 at the World Cup.

The Bayern Munich forward scored his ninth World Cup goal in as many games to give Germany a routine win at a rain-soaked Arena Pernambuco in Recife.

The rate at which Muller is scoring in World Cup games is matched only by Brazil legend Pele, who also found the net nine times in his first nine matches in the tournament.

The 24-year-old German is now just six goals behind the all-time scoring record, which is jointly held by Muller's team-mate Miroslav Klose and former Brazilian striker Ronaldo.

This was a frustrating afternoon for the United States and their travelling army of fans. They failed to force Germany goalkeeper Manuel Neuer to make a save of note but their qualification was assured by Portugal's 2-1 victory over Ghana in Brasilia.

The US will now travel to Salvador to take on the much-fancied Belgians on Tuesday. Germany will play the runners up of Group H in Porto Alegre on Monday.

Before the game, much had been made of the suggestion that both sides might play for a convenient draw that would take each of them through. But with US coach Jurgen Klinsmann, who previously managed Germany, facing off against his protege Joachim Low, neither team took a backward step from the first whistle.

Germany, playing their familiar passing game at a patient tempo, carved out a series of early chances.

On three occasions Bayern Munich defender Jerome Boateng found space wide on the right flank and fizzed fierce low crosses into the penalty area, while Arsenal's Mesut Ozil came closest to scoring, stepping away from Matt Besler's challenge to test United States goalkeeper Tim Howard.

Germany had to wait until the 55th minute to make the breakthrough, however, having seen Ozil and substitute Miroslav Klose go close.

It was a cross by the former that created the goal with Arsenal team-mate Per Mertesacker heading powerfully at goal and forcing Howard to push the ball into the path of Muller.

The forward struck his shot first time and it flashed beyond Howard before he could react to put Germany ahead.

The United States did show spells that suggest they will not be easy to beat in this tournament. Michael Bradley was at the heart of their best work, setting the tone with his tenacity in the tackle and his ability to keep possession under intense pressure.

The Toronto midfielder created the USA's best chance of the game, finding Kansas City forward Graham Zusi, whose shot curled narrowly over the bar, but Bradley's touch let him down just as a shooting opportunity presented itself moments before half-time.

The midfielder allowed his frustrations to get the better of him as he caught Muller with his studs raised and was fortunate to escape a booking.

After half-time the USA improved. Alejandro Bedoya saw a shot blocked after a fluent move down the USA right, while Clint Dempsey headed just over late on.

And although Germany closed out the game, when the result was confirmed in Brasilia, the United States also had something to celebrate.

USA coach Jurgen Klinsmann: "It's huge for us to reach the last 16. We wanted at least a tie out of the game and maybe at the beginning we had too much respect.

"But overall there was tremendous energy and effort from all of the side. It's huge for us to get out of group - everyone said we had no chance but we took that chance. Now we want to prove a point."

Germany coach Joachim Low: "I knew it would be difficult today and it was. USA defended deep, they were well organised, but I have to say we dominated, denying them good chances in the process.

"Our midfield was great today - they were dynamic and never stopped running.

"It wasn't easy for USA - everyone thought Portugal would qualify, but they've done it. They're tough opponents and they've deserved it."

Germany forward Thomas Muller: "We were dominant. All the Americans did was sit back deep in their own half, and when that happens, it just becomes a patience game.

"But sometimes even I manage to have a bright idea - I spend the whole day training like I'm obsessed anyway."