INDIAN WELLS, Calif. — Rafael Nadal withdrew from the BNP Paribas Open on Saturday, done in once again by a knee injury.
He had been set to play longtime rival Roger Federer in the semifinals.
A sombre Nadal announced his withdrawal a couple hours before he was scheduled to take the court at Indian Wells Tennis Garden.
"I warm up today in the morning, and I felt that my knee was not enough good to compete at the level that I need to compete," he said.
The Spaniard's right knee flared up in the second set of his 7-6 (2), 7-6 (2) victory over Karen Khachanov in Friday's quarterfinals. He twice called for a trainer, who applied tape just below Nadal's knee. It was obvious that Nadal's movement was hampered.
Nadal said he won't play again until the Monte-Carlo Masters on clay in mid-April.
"I don't have doubts today that I will be ready for Monte Carlo," he said.
Knee problems have dogged the 32-year-old Spaniard for years, and they cut short his 2018 season after the U.S. Open in September. He was forced to quit two sets into his semifinal against Juan Martin del Potro.
Nadal choked up discussing his withdrawal last fall, and he appeared near tears on Saturday.
He admitted that he sometimes is sad because he feels at a disadvantage against his opponents due to his continued knee issues that force him to limit his practice and playing time.
Then he gathered himself, saying, "It's not the moment to complain much. With all this stuff, I still where I am today."
The year began promisingly enough. Nadal didn't drop a set in reaching his fifth Australian Open final, where he lost to Novak Djokovic. He's ranked No. 2 in the world and has a match record of 11-2.
"Still tough because I felt more or less OK during this beginning of the season in terms of my knee," he said. "Now it starts the process that I have to decide what direction we have to take to recover well and to recover as soon as possible."
Even with all of his injuries, Nadal indicated he has no intention of giving up playing on hard courts, the surface for two of the four Grand Slam events.
"My goal is to play on all the surfaces," he said.
It would have been the 39th career meeting between Nadal and Federer, who advances to Sunday's final in pursuit of a record sixth title at Indian Wells.
Federer will play either Milos Raonic or Dominic Thiem, whose semifinal was under way when Nadal was talking to reporters.
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