Real Madrid winger Vinicius Junior is out for up to six weeks with a hamstring injury, Spanish media reports said Monday.

Los Blancos confirmed the Brazilian's injury in a statement but did not specify his expected absence time.

Vinicius limped off injured against Celta Vigo on Friday early in Madrid's 1-0 win at Balaidos, which kept the team top of La Liga with a 100 percent record after three games.

The 23-year-old may not be fit by the time the Champions League starts on September 19, and is set to miss important La Liga matches against Real Sociedad and city rivals Atletico Madrid before then.

"(Vinicius) wanted to continue, so I don't think it was that serious, he tried, then it hurt a bit," said Madrid coach Carlo Ancelotti on Friday, with the injury turning out to be more serious than first thought.

Spanish reports said the forward would miss between a month and six weeks, potentially missing five matches, four in the Spanish top flight and one in Europe.