Germany's Thomas Muller plundered the first hat-trick of this goal-laden World Cup as Portugal crumbled in the early afternoon heat in Salvador.

The Bayern Munich star scored an early penalty and then a goal from open play in each half to give the 2010 semi-finalist the perfect start at Arena Fonte Nova.

Central defender Mats Hummels scored Germany's other goal on an afternoon when just about everything that could go wrong did go wrong for Cristiano Ronaldo and Portugal.

Not only did they lose centre forward Hugo Almeida and Fabio Coentrao to serious-looking injuries, they also saw central defender Pepe sent off with the score at 2-0 in the first half for a completely unnecessary headbutt on Mueller. 

The forward did seem to go down a little easily as Pepe caught him across the jaw as two men tussled for possession 30 yards form goal. But only Pepe will know why he then bend down to push his forehead in to Muller’s temple as the German sat on the ground.

Serbian referee Milorad Mazic really had no choice but to send Pepe off and he will now play no further part in the group stages.

Germany were every bit as ruthless as we would have expected them to be. Muller’s finishing was calm and unfussy while midfielder Sami Khedira pushed him to the line for the man-of-the-match award.

Nigeria, Iran play out first draw

Nigeria and Iran played out the first goalless match of the 2014 World Cup in their Group F clash at the Baixada Arena, Curitiba, on Monday, leaving both sides still chasing their first victory at a finals since 1998.

While Iran could take some small satisfaction in keeping a clean sheet for the first time since their debut in 1978, the bore at the Baixada arena stood out like a suit salesman on Copacabana beach.

With Lionel Messi's Argentina, installed as clear Group F favourites, and exciting debutants Bosnia still to come, the other two look destined for an early exit unless they can raise their game considerably.

Both teams were whistled and booed off the field by the largely Brazilian crowd of 39 000 after a first half that looked shockingly meagre compared to the goal feasts served up elsewhere.

Iran packed their defence as expected and Nigeria, with Emmanuel Emenike rarely posing a threat as the main target man for the African champions, squandered 

their chances with long balls to nowhere and passes straight to opponents.

The Super Eagles had the ball in the back of the net after seven minutes in a goalmouth scramble but Ecuadorean referee Carlos Vera, perhaps harshly, ruled it out for a push on goalkeeper Alireza Haghighi.Ogenyi Onazi then drilled a shot wide two minutes later.

Iran came closest to breaking the deadlock in the 33rd minute when goalkeeper captain Vincent Enyeama produced a fine save to beat out Reza Ghoochannejhad's header from their first corner of the game.

Nigeria defender Godfrey Oboabona made an early exit from the fray, replaced by former captain Joseph Yobo on the half hour after earlier receiving treatment on the touchline following a heavy tackle.

Nigeria coach Stephen Keshi warned on Sunday that the African sides were as good as any in Brazil and could win the tournament, but on Monday's evidence they will not be celebrating in Lagos.