Coentrao misses Portugal training
The full-back scored in his country's final FIFA World Cup warm-up fixture - a 5-1 triumph over the Republic of Ireland on Tuesday - but there will now be fears over his fitness ahead of Portugal's tournament opener against Germany on Monday.
However, Portuguese Football Federation vice president Humberto Coelho was quick to allay those concerns, a day after the national team arrived in Brazil.
"It's nothing to worry about," he insisted. "It's just a one-off situation.
"Quickly he will be fine and back to training."
As well as Germany, Portugal will face the United States and Ghana in Group G.