Former player and now analyst Jimmy Arias has been speaking about Rafael Nadal's chances on clay in the coming years, airing his scepticism that the Spaniard will be able to stay at the top.
As quoted by Tennis World USA, Arias said: "I never conceded the French title to Nadal, like some others did.
"I’ve often felt like Rafa is on the verge of being beatable, but then he’d get to Roland Garros and win."
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He followed up by saying: "He proved me wrong every time a lot of times. But now he’s showing some wear in that armour."
Nadal himself is yet to respond to Arias' comments, and the 'King of Clay' is currently recovering from a foot injury sustained during the American hard court season, but had been troubling him since the most recent French Open.
With a record 13 titles at Roland Garros, Nadal stands head and shoulders above any player to compete at the clay court Grand Slam, however, suffered defeat to Novak Djokovic in the semi-final this year.

Jimmy Arias returns a shot to Todd Martin during the second set of their ATP Champions Tour match on Friday, February 18, 2011, at the Delray Tennis Center in Delray Beach, Florida. Martin won 6-2, 7-5.

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At the Citi Open, he was upset by Lloyd Harris in the third round, subsequently withdrawing from the Canada and Cincinnati Masters before the US Open.
At Roland Garros, he fell to Novak Djokovic in four sets 3-6 6-3 7-6 6-2.
He has since fallen to eighth in the rankings, and sits out of the nearing ATP World Tour Finals with this same foot injury.
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