Barcelona forward Ronaldinho will miss Brazil's forthcoming World Cup qualifiers against Peru and Uruguay and at least four Spanish Primera Liga matches after a scan confirmed that he had torn a muscle in his right thigh.

The Catalan club said on Monday that the Brazilian international would be out of action between four and six weeks depending on how well he responded to treatment.

The injury will mean that Ronaldinho, who joined Barcelona from Paris St Germain in a deal worth €30 million at the start of this season, will almost certainly miss the eagerly awaited clash against arch-rivals Real Madrid at the Nou Camp on December 6.

The 23 year-old World Cup winner sustained the injury during Barcelona's 2-1 victory over Real Betis on Sunday, a win that pushed his side up into fourth place in the league table.

He had been due to travel to Brazil on Monday to join the rest of the national squad, but it is not clear whether he will make the trip or remain in Barcelona for treatment.

Brazil, who top the South American World Cup qualifying group with a maximum six points from two games, play Peru on November 16 and Uruguay three days later.

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