The France international tore ligaments just above his ankle in the opening minutes of his team's 2-0 defeat to Italy as they crashed out of Euro 2008 on Tuesday.

Ribery underwent surgery Munich on Thursday after which chairman Karl-Heinz Rummenigge claimed the operation had "gone perfectly".

However, despite being given a recovery time of seven to eight weeks, Bayern have been forced to recalculate that figure with the 25-year-old set to go under the knife again in six weeks' time to have metal plates removed.

The operation will put Ribery's recovery back and rules him out of the first few Bundesliga fixtures in August.

"If everything runs perfectly, then he will be back in full action in September," Dr Ludwig Seebauer, who carried out the surgery, told the club's website.

The Frenchman will be on crutches for four weeks before commencing physiotherapy at Bayern's training ground.

The Bundesliga season begins on August 15 while Bayern will be involved in the first round of the DFB-Pokal a week earlier.