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. @RafaelNadal is retired from the tournament due to a right knee injury. We wish Rafa a speedy recovery.
Roger Federer qualifies for the final walk.
# BNPPO19 https://t.co/XXahjOyOXn
Nadal was the victim of the problem in Friday's victory against Karen Khachanov in eight sets. He had his knee stuck but he was playing in a match that required winning both sets at tie-break, 7-6 (2), 7-6 (2).
@RafaelNadal back in the field after receiving knee treatment
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Federer will wait for the winner of Dominic Thiem's meeting with Milos Raonic later on Saturday. Aged 37, he will now be considered the favorite to win this title for the sixth time.
It would be a record, with Federer tied with Novak Djokovic on five wins.
Nadal would have thought he could deny the story of Federer earlier than expected. However, the Spaniard was not convinced that his knee would hold:
"I warmed up today and felt that my knee was not good enough to compete with the level I needed to compete in the semifinals" – Rafael Nadal
His decision is cautious, but it prevented fans from attending the 39th meeting between these two rivals in history. They have produced some of the most memorable games in tennis history, including the final epic of Wimbledon in 2008, as well as the deciding game that will determine the outcome of the Australian Open two years ago.
Federer v Nadal greatest ATP points: a wire
What better place to start than their very first meeting, in Miami? … https://t.co/PVug8fP4Vi
While Federer is still in great shape, Nadal is starting to look vulnerable because his body is failing him.
Persistent injuries prevented him from taking part in "a single hard tournament in 2018", according to BBC Sport. The same source reported how Nadal retired during the quarter-finals of this year's Australian Open and the last four of the US Open.
"It's hard for me to accept everything I live in my career. Sometimes I'm sad because I'm at a disadvantage to all my opponents. "- Rafael Nadal
"[I need to] be positive and grateful for all that tennis has brought me. I feel lucky for everything I've done in my life and in the world of tennis. " – Rafael Nadal
Another setback should cast doubt on the ability of one of the greatest players in the sport to continue to compete at its highest level.