World number one Novak Djokovic has pulled out of the Western & Southern Open due to his exertions at the Olympic Games in Tokyo.
Djokovic, a two-time winner of the event in Cincinnati, said in a statement on Monday that he planned to give his body a rest and spend some time with his family ahead of the start of the US Open on 30 August.
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The Serb is bidding to become only the sixth singles player in history to complete a calendar Grand Slam. Victory at Flushing Meadows would also make him the first man to win 21 major singles titles, edging him ahead of Roger Federer and Rafael Nadal.
However, he has competed on a hectic schedule since the start of the Australian Open in February.
Djokovic had hoped to add an Olympic gold medal to his potential Slam clean sweep, but saw his Tokyo 2020 hopes ended by German Alexander Zverev in the semi-finals.
He then lost the bronze medal match to Spain’s Pablo Carreño Busta and withdrew from the mixed doubles, at the same stage, with a shoulder injury.
"Dear Nole Fam, I wanted to share with you that I am taking a bit longer to recover and recuperate after quite a taxing journey from Australia to Tokyo," Djokovic wrote on social media.
"Sadly, that means I won’t be ready to compete in Cincinnati this year so I’ll turn my focus and attention to US Open and spend some more time with family. See you in New York soon!”
Five former men's champions, Andy Murray, Daniil Medvedev, Grigor Dimitrov, Marin Cilic and Nadal, remain in the men's main draw in Cincinnati, which is scheduled to get under way on Sunday.
Serena Williams, Victoria Azarenka, Madison Keys, Garbine Muguruza and Karolina Pliskova are among the big names in contention for the women's title.
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