Argentina legend Diego Maradona says Germany's powerful performance in their 4-0 win over Portugal is cause for concern amongst the other FIFA World Cup™ favourites.

"We saw a devastating Germany, a Germany who roamed around with perfection," the 1986 World Cup-winner told his Venezuelan television show 'De Zurda'. "They caused a bit of worry with their physical strength."

Thomas Muller became the first player to claim a hat-trick at Brazil 2014 as Cristiano Ronaldo's Portugal were outclassed, after centre-back Pepe's first-half dismissal in Salvador. Former Argentina coach Maradona got a taste of Germany's power four years ago in South Africa when his team was hammered 4-0 in the quarter-finals.

Maradona said he was impressed by the Germans' "very, very intelligent lines of running" against the Portuguese in their Group G opener.

"If Germany keep this rhythm, then they must be taken seriously," Maradona added. The Argentina legend has already nicknamed Germany's hat-trick star Muller 'El Flaco' - the Skinny One. "He has no muscles, but today he tore them apart," added an impressed Maradona.