Spring and clay-court season are normally the time of the year that Rafael Nadal shows his dominance. His uncle, who also is his coach, isn't sure that's going to happen in 2015.

Tennisworldusa.org reported that Toni Nadal fears that his nephew's past injury issues and his infrequent play may signal the end of his reign in the French Open this year.

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Nadal has nine French Open titles, including five in a row, and has lost just one match at Roland Garros. Despite winning the title in 2014, Nadal suffered myriad injuries that curtailed his year.

So far in 2015, he has engaged in limited work, although the No. 3 player in the world (and former No. 1) did advance to the quarterfinals of the Australian Open with almost no preparation, and he won his 46th career title on clay at the Argentina Open.

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But he still is not close to being prepared for the French Open, which takes place in May.

"I believe it is a mental issue. When someone isn't feeling at his best mentally, that affects all other aspects, including the physic and the movements. What is the cause for this mental problem? Rafa is missing consistency. He has based all his career on constancy and consistency, and now he is missing it. To get back to competition had a price to it, and now we are paying for it" Toni told the Spanish press, on online platform El Confidential, tennisusaorg.om reported.

"The win in Buenos Aires sure worked as a positive motivational boost, but that won't be enough to play at the best in Indian Wells and Miami. We lacked in consistency, and now we are finding it back."

The problem, Toni says, is that Nadal's play goes into periods of wild swings of inconsistency.

"It happened to him in Doha, where he played very well in the first set and then he left the match," Toni said. "In Australia he faced the same issue. He played good matches and then against Berdych he has been a disaster in the first two sets. In Rio the same thing, he stopped playing after the first set. These things started happening frequently most recently and that causes doubts and fears."

Which could make the 2015 French Open more interesting.

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