Cristiano Ronaldo will be back with Real Madrid on August 10. The superstar, who injured his knee in the Euro 2016 final, confirmed his return date to AS, and now his availability for the start of the season is in doubt.

As a player who played in an international tournament, Ronaldo is entitled to three weeks off before he has to report back to his club. But Real Madrid already agreed to grant him more time. Whether it was for regular rest or related to his knee injury was never made clear.

Ronaldo has been quiet about his injury and when he expected to return. Real Madrid haven't commented much on his status either. He does have a trainer with him at all times, including on vacation in Ibiza, so he is dilligently rehabbing, but appears to be a bit off from getting back on the field.

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It doesn't matter much that Ronaldo will miss the Super Cup. It's just a glorified friendly. But an August 10 return will put his availability for the start of the La Liga season in doubt. Real Madrid open their domestic campaign on August 21 against Real Sociedad and it's still unclear what type of health his knee will be in by then.

Even if his knee is ready to go on August 10, it's tough to imagine Ronaldo being able to get back to full fitness in just 11 days. Seeing as Real Madrid missed out on winning the league by a single point last season, every match in La Liga is crucial and not having Ronaldo -- or at least not a fully fit and in form Ronaldo -- could be a blow to Real Madrid right from the start.

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