Barcelona full-back Douglas will miss the start of the 2015-16 campaign because of a hamstring injury.
Douglas, 24, sustained the problem in the 16th minute of Barca's penalty shootout defeat to Chelsea on Tuesday in Washington DC and was replaced by Sergi Roberto.
The match ended 2-2 and was then won 4-2 on penalties by the Premier League champions.
A statement from Barcelona read: "Douglas has suffered a hamstring injury in his right leg. He is expected to be out for around eight weeks."
Douglas will miss next month's the UEFA Super Cup against Sevilla as well as the Spanish Super Cup against Athletic Bilbao.
He will sit out the first six La Liga games but could return to action on Oct. 3 when Barca host Sevilla.
Head coach Luis Enrique said after Tuesday's defeat to Chelsea on his club's official website: "The only negative note of this game is Douglas's injury. Any injury is always bad news and makes me sad."
Luis Enrique was pleased with his team's performances on the club's preseason tour of the U.S., which has now come to a conclusion.
He said: "We have been able to get playing time against top quality opposition, we have had the chance to feel the support of lots of fans, who have been the majority in the stadia and we have been able to promote the club. We go back home happy."
Barcelona return to Spain on Wednesday and will next take on Fiorentina in the International Champions Cup in Florence on Aug. 2.
Three days later, Luis Enrique's men host Roma in the Joan Gamper trophy at the Camp Nou.
Barca face Sevilla in the European Super Cup final on Aug. 11 in Tbilisi, Georgia.