CINCINNATI (Ohio) • Rafael Nadal was thrilled on Monday to learn he would return to world No. 1 for the first time in three years but felt sorry it came because Roger Federer withdrew from this week's Cincinnati Masters tournament.

Third-ranked Federer said that he injured his back at the ATP tournament in Montreal, where he lost in Sunday's final to Germany's Alexander Zverev in a key hard- court tune-up for the US Open.

Federer, this year's Wimbledon and Australian Open champion, was the only player who could have denied second-ranked French Open champion Nadal the top spot in next Monday's rankings.

"For me, to be in that position is something very special," the Spaniard said.

"I have the passion and love for the game. That's why I'm able to be back in that position again."

It is the first time Nadal has been world No. 1 since July 2014. The 31-year-old, who won his 15th Grand Slam title this year at Roland Garros, will overtake Britain's top-ranked Andy Murray, who withdrew from Montreal and Cincinnati with a hip injury.

OLDER BUT WISER Of course we're not 20 years old any more. We're not playing all the weeks. That's part of the sport. I skip many more events than the rest of my competitors. RAFAEL NADAL, 31, who has struggled with knee injuries for many years, on planning his schedule carefully.

Nadal, who has spent 141 total weeks in the top spot, has struggled with knee injuries since first becoming world No. 1 in August 2008 after a Cincinnati semi-final run. He admitted doubting he could ever regain the top spot after so many years.

"If you don't have doubts, it's because you are very arrogant and I'm not very arrogant," he said.

"There's a young generation up and coming. It's very tough to come back and be No. 1."

Nadal knows that while he will claim the upper hand no matter how he fares this week, the year's final Grand Slam event starting in New York on Aug 28 will have a major role to play in the fight with Federer for the top rank.

"Roger and I are having great seasons," Nadal added.

"One of us will have the chance to have that position for more weeks. I'm going to try and do my best this week and see what happens."

Federer, a seven-time champion on the Cincinnati hard courts, apologised but said he needed to rest with the US Open so near.

"I am very sorry to pull out of the Western and Southern Open as I always enjoy playing," the Swiss star said. "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 was also sorry to see Federer join the list of players absent this week, which includes Murray, Serbia's Novak Djokovic, Japan's Kei Nishikori and Swiss Stan Wawrinka.

"It's bad news for Roger he's not playing," Nadal said.

"I'm sorry for all of them. I hope they have good recovery. We need to see them back for the sport.

"Of course we're not 20 years old any more. We're not playing all the weeks. That's part of the sport. I skip many more events than the rest of my competitors."

Nadal, who was upset by 18-year-old Canadian Denis Shapovalov in the Rogers Cup round of 16 last week, will face Frenchman Richard Gasquet in the round of 32 in Cincinnati today.

AGENCE FRANCE-PRESSE, REUTERS

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