Nadal's classy message to injured Federer

Roger Federer's latest injury scare handed Rafael Nadal the No.1 ranking, and Rafa has responded with a classy message to his great rival.

The ATP tour has almost turned into a who's who of the walking wounded, with Federer the latest big name to go down injured.

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While Federer's absence from the Cincinnati Masters is only precautionary ahead of the US Open, he joins Andy Murray, Novak Djokovic, Stan Wawrinka and Kei Nishikori in the current casualty ward.

Murray hasn't played since Wimbledon and is no guarantee of turning out for the US Open, while Djokovic, Wawrinka and Nishikori will all miss the final grand slam of the year.

Nadal has capitalised on his rivals' absences and will return to World No.1 for the first time since 2014 when the latest rankings are released on Monday.

But rather than revel in his good fortune, Nadal has sympathised with the unfortunate plight of his opponents.

"I have been in that position more than all these players that are out now," he said after beating Richard Gasquet to reach the third round in Cincinnati.

"I know how tough it is. I'm very sorry for all of them and I wish all of them a fast and good recovery.

"But at the same time I tell you Roger didn't have a lot of these things during his career. Novak the same. Andy the same. Stan, I don’t think he had a lot of issues.

"I'm the only one of these top players that missed a lot of important tournaments in my career. More than nobody else, I know how tough it is.

"But the only thing that you can do when these kind of things happen is accept and keep going."

Federer, who is usually a regular in Cincinnati, said he had picked up his injury in Montreal, where he lost to Germany's Alexander Zverev in the final.

"I am very sorry to pull out of the Western and Southern Open as I always enjoy playing here," Federer said in a statement issued by the tournament.

"Cincinnati has some of the best fans in the world and I am sorry I will miss them. Unfortunately, I tweaked my back in Montreal and I need to rest this week."

Nadal has spent 141 weeks at No.1 since first ascending there after reaching the Western and Southern semi-finals in 2008.

"It's been tough to get back to No.1," Nadal said.

"I'm happy to have the chance to be in that position."

with AAP