BARCELONA (AFP) - Troubled Barcelona were dealt a new blow ahead of the start of the Spanish league season when Luis Suarez was ruled out for a month with a knee injury on Thursday (Aug 17).

The Uruguayan striker suffered the injury in the second half of Wednesday night's 2-0 defeat away to Real Madrid in the second leg of the Spanish Super Cup, although he played on to the end as Barcelona lost 5-1 on aggregate.

"Luis Suarez will be out of action for around four weeks. Tests carried out on Thursday morning confirm that the Uruguayan has a distension in the posterior articular capsule in his right knee picked up in the second half of the Clasico on Wednesday in the Santiago Bernabeu," said Barcelona in a statement in English published on their website.

The news means Suarez will miss Barcelona's first three games of the season in La Liga, at home to Betis on Sunday, away to Alaves on Aug 26 and at home to Espanyol on Sept 9.

He will also miss Uruguay's World Cup qualifying ties against Argentina on Aug 31 and Paraguay on Sept 5 and is likely to sit out his club's first Champions League group game on Sept 12 or 13.

Barcelona also revealed that defender Gerard Pique is a doubt for the meeting with Betis due to a groin strain, meaning further bad news for the Spanish giants whose summer has been overshadowed by the sale of Neymar to Paris Saint-Germain.