NEW YORK, Aug 28 — Rafael Nadal targets a fifth US Open and 23rd Grand Slam title in New York from next week with his path to the title no longer blocked by Novak Djokovic, whose refusal to get vaccinated has ruled him out of a second major this year.

Nineteen years after making his debut, the 36-year-old Nadal drags his injury-prone body into a tournament he won in 2010, 2013, 2017 and 2019, the year of his last appearance.

The Spaniard has had to sit out the US Open four times in his career and there are once again fresh doubts over his physical ability to survive a gruelling two weeks at Flushing Meadows.

Since an abdomen injury forced him to hand Nick Kyrgios a walkover into the Wimbledon final, Nadal has played just once -- a first-up loss to Borna Coric in Cincinnati.

Nadal admitted on Friday that he had been protecting his injury in Cincinnati but had been able to practice with intensity in the build-up to the US Open.

"I take it very easy in the Cincinnati, too, in the practices. The match, I try my best without putting all the effort there on the serve," Nadal said.

"I hope to be ready for the action. That's the only thing that I can say.

"Taking care with the serve, being honest. But in general terms, yes, I am practicing at high level of intensity."

Nadal has become accustomed to overcoming setbacks, winning a 14th French Open in June despite playing the whole tournament with pain-killing injections in his foot.

An added incentive for Nadal is the opportunity to reclaim the world number one spot from defending champion Daniil Medvedev, the man he defeated in the 2019 final.

While Nadal trains in New York, career-long rival Djokovic will remain in Europe after finally giving up hope of a last-minute change of Covid policy by the US authorities.

The famously unvaccinated Djokovic, who won the last of his three US Open crowns in 2018, is barred from entering the United States for refusing to take the vaccine.

The 35-year-old, who saw his bid for a first men's calendar Grand Slam since 1969 ended by Medvedev in the 2021 US Open final, hasn't played since securing a seventh Wimbledon title last month, a victory which extended his Slam record to 21.

His controversial vaccination stance also saw him deported in January from Melbourne, where he had been hoping to defend his Australian Open title.

"Not having one of the best players of the history in the draw of Grand Slam is always an important miss, no?" was Nadal's take on Djokovic's absence.

"Tough for the fans, tough for the tournament, tough for the players, too, because we want to have the best field possible."

With Roger Federer still absent from the tour and with question marks over Nadal's fitness and Djokovic's absence, the race for the men's title is likely to be as open as recent years.

Marin Cilic, Stan Wawrinka, Dominic Thiem and Medvedev have all broken the New York stranglehold of the "Big Three" since 2014.

Medvedev will be especially fired up having been banned from Wimbledon along with all other Russian players following the invasion of Ukraine.

On his reappearance on the tour following the All England Club cold shoulder, the 26-year-old claimed the hardcourt title in Los Cabos.

World number two and 2020 runner-up Alexander Zverev misses out through injury while fourth-ranked Carlos Alcaraz, a quarter-finalist in 2021, looks to convert potential into a maiden Slam triumph at 19.

"I feel stronger and more prepared than the last year," Alcaraz said. "I have played long matches, tough matches this year against the top players. I think I'm more ready in this tournament than last year."

Apart from Felix Auger-Aliassime, a semi-finalist last year, the rest of the current top 10 have endured a bittersweet relationship with New York.

Stefanos Tsitsipas, Casper Ruud, Cameron Norrie and Hubert Hurkacz have all yet to make the second week. — AFP