Rafael Nadal has offered some sympathy for Novak Djokovic after his disqualification from the US Open, but also said it is important to have "self-control".

With Nadal absent, world No 1 Djokovic was a huge favourite to win the title in New York, but his run came to a sudden end in the fourth round against Pablo Carreno Busta when he hit a lineswoman with a ball.

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Had Djokovic won the title he would have moved to 18 Grand Slam titles, one behind Nadal and two behind Roger Federer in the battle for all-time greatness.

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"The consequences have been always the same. Nothing new on that," said Nadal in a news conference at the Rome Masters, where he will resume his season this week after a seven-month hiatus caused by the Covid-19 pandemic.

"Novak was unlucky. [But] The rules say clearly that's a default. Sorry for him. He had an opportunity there. But in some way you should not be doing this. It's very unfortunate, very unlucky situation. But it's important to have the right self-control on the court, because if not, you can be unlucky."

Nadal was one of several players to opt out of playing at the US Open because of his concerns about travelling during the pandemic.

Dominic Thiem, the man Nadal beat to win the last two French Opens, claimed his first Grand Slam title at Flushing Meadows, coming back from two sets down to beat Alexander Zverev in a gripping final on Arthur Ashe Stadium on Sunday.

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Thiem's victory ended a run of 13 Grand Slam titles won by either Nadal, Djokovic or Federer and made him the first new major winner since Marin Cilic in 2014.

"Happy for Dominic. He is somebody that deserves to win a big title, super hard worker. Very focused on his goals. Good person, good human person. He deserves it," said Nadal, who will be aiming to win a record-extending 13th French Open when the rescheduled clay-court event starts at the end of September.

Nadal will open in Rome against Carreno Busta, who made the semi-finals in New York.

Additional reporting by Reuters

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