Rafael Nadal fell behind David Ferrer in the ATP rankings and out of the top four.
Jessica Kluetmeier/SI

One week ahead of his expected return to tennis, Rafael Nadal says his left knee is still causing him pain.

The 26-year-old Spaniard is scheduled to play next week in Chile before heading to tournaments in Brazil and Mexico.

Speaking Wednesday on the island of Mallorca, Nadal says that although his knee is looking better, "sometimes it still hurts ... but I have to start sooner or later."

Nadal says playing at the three Latin American tournaments "will be very useful," adding he is "fine, enthusiastic," after not playing since losing to Lukas Rosol in the second round at Wimbledon.

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