Thomas Muller left the Green Point Stadium pitch as one of Germany's heroes today, after his glancing header helped them into the 2010 FIFA World Cup South Africa™ semi-finals. However, the Bayern Munich 20-year-old is poised to miss the biggest match of his career.

Muller got his fourth goal of the tournament - after one against Australia and two against England - in just the third minute to give Germany a dream start to their quarter-final with Argentina. They went on to win 4-0.

Fantastic. Everything went superbly and to send Argentina packing 4-0, well, what can you say?

Germany's Thomas Muller

"Fantastic. Everything went superbly and to send Argentina packing 4-0, well, what can you say?" he said afterwards. "We did it as a team and I can't pick out any individuals. We all pulled together for this and it's just great."

But Muller's joy was tinged with regret after he picked up another yellow card to go with the one he got against Ghana, for controlling the ball with his hand on 35 minutes. It means he is not eligible to play in the last-four tie against either Paraguay or Spain in Durban next week, as Germany go in search of their fourth FIFA World Cup title and first since 1990.

"I am hoping my colleagues will do the business in the semis so I can get back and have a shot at that," he said, when asked about his chances of winning the adidas Golden Boot.

Joachim Low said Muller's absence in the semi-finals was a big blow, but said the team had enought depth to cover. "The fact that we won't have him is a serious blow because he has shown how dangerous he is," said the Germany coach. "But in the past we have been able to replace people like Muller, and we will continue to do so as we move forward."

While Muller misses out, he can at least take consolation from having made sure Diego Maradona will never again forget who he is, after the Argentina coach said he mistook the Bayern Munich forward for a ballboy when they first met. The youngster has made a name for himself in South Africa and is a contender for the tournament's Hyundai Best Young Player Award.

The fact that we won't have him is a serious blow because he has shown how dangerous he is.

Germany coach Joachim Low on Thomas Muller being ruled out of the semi-finals

He was little known outside Germany when he made his debut in a 1-0 friendly defeat by Argentina in Munich in March, and attended the post-match press conference as his country's great new hope alongside the Argentina coach. Maradona joked that he thought the ballboy had arrived and felt so slighted that he stormed off and refused to return until the German left the stage to him alone.

But with four goals at this FIFA World Cup and a UEFA Champions League final appearance, plus the German league and cup double, under his belt, Muller is now a household name - and one Maradona will not forget in a hurry.