Felix Auger-Aliassime has warned Rafael Nadal he will need a 'monumental effort' to win Roland Garros this year.
Auger-Aliassime took Nadal to the limit in their round of 16 clash on Sunday, with the Spaniard taken to a rare fifth set on clay.
For a while the Canadian looked on the verge of a big upset, but Nadal was able to summon his best tennis at the right time to win it 3-6, 6-3, 6-2, 3-6, 6-3.
Nadal will now face Novak Djokovic in the quarterfinal as he bids for what would be a 14th French Open title and a 22nd career major.
Auger-Aliassime, though, believes Nadal could no struggle for fitness later in the tournament because of their marathon clash.
"I wish Rafa the very best, I admire him greatly in everything that he's done," Auger-Aliassime told reporters of Nadal. "He's somebody who I really like, and so I wish him the very best for the next match.
"But then I think that he also knows that it's going to be difficult.
"We played for a long time today and it's still the quarter-finals and afterwards there's still two more matches to win to win the tournament. Rafa is coming here to win the tournament.
"So as I said, I really wish him the very best, but it will be a monumental effort for him, I think, to win.
"But as he and Novak have always done, they will give it their all right through to the end and it will be a great battle."
Novak Djokovic is the only man to have ever beaten Rafael Nadal multiple times at the French Open, with the latest of those wins coming in the semi-finals last year.
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