Portugal full-back Fabio Coentrao is out of the World Cup after suffering a thigh injury dealing another blow to the already fragile morale of the team, the Portuguese Federation (FPF) said Tuesday.

Coentrao was forced off after 65 minutes of his country's disastrous opening Group G 4-0 thrashing by Germany on Monday.

Coentrao suffered a "second grade tear of the adductor longus muscle in the right thigh," said the FPF statement on their website.

It was a bruising match for Portugal, who had Pepe sent-off for a petulant head-butt on hat-trick hero Thomas Mueller.

The 26-year-old Real Madrid left-back Coentrao was amongst three players to undergo MRI scans on Tuesday.

Forward Hugo Almeida, who lasted only 28 minutes in Salvador, suffered a first grade tear in his left hamstring while goalkeeper Rui Patricio also suffered a grade one tear in his thigh.

Both are expected to return to full fitness before the end of the tournament.