Football-mad Germans have snapped up the "lucky" blue cashmere sweater that German coach Joachim Low gives partial credit for his side's 2010 FIFA World Cup™ winning streak.

The jumpers have flown off the shelves, upscale clothier Strenesse said, with fans having to travel to the neighbouring Netherlands, home of the Germans' fellow semi-finalists, to get their hands on the garment Low has worn at three German victories. "We're completely out of stock," a company spokeswoman told AFP.

The 50-year-old's backroom staff have demanded Low wear the cobalt cashmere in the semi-final against Spain on Wednesday, as he has every time Germany have scored four goals in a match at the finals in wintry South Africa. Low, who replaced Jurgen Klinsmann after Germany 2006, donned the v-neck in the opening 4-0 humbling of Australia, the 4-1 destruction of old foes England and then the 4-0 humiliation of Argentina on Saturday - the first time that a team has thrice scored four goals in the finals.

He told reporters that "Germany's miraculous sweater", as the daily Bild has dubbed it, might just have magic powers. "I am not really superstitious but (deputy coach) Hansi Flick and others basically forced me to put it back on - it gave us four goals at each of the matches," the dapper trainer said. "There's no way I'm changing my sweater, or even washing it."

Despite sweltering temperatures in much of Germany, shoppers cannot get enough of the €199 ($US250) sweater in "Jogi" blue. Those willing to sacrifice authenticity for comfort can purchase cotton or mixed-blend lookalikes, Strenesse said.

Meanwhile desperate fans in Berlin were coveting the Jogi look. "I wanted one for my dad - he would have been so happy," 26-year-old Anna Gruber said as she surveyed an empty shelf at Strenesse. "He already has the Jogi shirt."

During the UEFA EURO 2008, the trim Low wore a snugly tailored white button-down that also became an iconic fashion statement. Then the Germans made it to the final, before losing to Spain.