Barcelona captain Leo Messi is out of action less than two weeks ahead of the opening of La Liga season after injuring his right calf in training on Monday.
The Argentina star has already been ruled out of the team's trip to Florida for a one-off friendly against Napoli in Miami on Wednesday.
"Tests carried out have diagnosed a grade 1 calf strain," the Spanish champions said in a statement, an injury that can require around two weeks of recuperation.
"Messi will remain in Barcelona and will now not travel to the USA for the club's tour. His availability to come back to action will be dictated by his recovery from the injury."
The club open the new La Liga campaign at Athletic Bilbao on August 17. Messi had been on vacation since Argentina finished third in the Copa América last month.
It's the latest round of bad news for the Albiceleste star. Messi was banned from playing for his national team for three months and fined US$50,000 last Friday by CONMEBOL after he heavily criticised the South American football governing body during the Copa América.
The 32-year-old Barcelona forward had accused CONMEBOL of "corruption" after he was sent off against Chile during the third-place play-off during the tournament in Brazil, which ended last month.
Messi was angered by two incidents during the June-July tournament hosted by bitter rivals Brazil.
The Albiceleste were denied two penalty claims in their 2-0 semi-final defeat to the hosts, after which Messi claimed Brazil were "managing a lot in CONMEBOL these days."
And when he was harshly dismissed in the next game, which Argentina went on to win 2-1, he couldn't contain his anger.
"Corruption and the referees are preventing people from enjoying the football and they're ruining it a bit," Messi said.
He was given his marching orders after a first-half scuffle with Chile captain Gary Medel in which television pictures suggested he'd done little wrong.
The CONMEBOL statement on its website didn't specify why Messi was being punished but said it was related to articles 7.1 and 7.2 of its disciplinary regulations.
One such clause refers to "offensive, insulting behaviour or making defamatory protests of any kind."
Another clause mentions "breaching the decisions, directives or orders of the judicial bodies."
The ban means only that Messi will miss a handful of friendly matches as Argentina's next competitive fixture is not until the South American qualifiers for the 2022 World Cup in Qatar begin in March.
However, he has already received a one-game ban from CONMEBOL for his red card against Chile meaning he'll miss the first of those.
Argentina have two friendlies lined up in the United States in September against Chile and Mexico and another in October away to Germany.
Messi would miss all three of those but be free to play for his country again in November.