Novak Djokovic‘s hard-court season began on a forgettable note. After more than a month away from the Tour, the Serb received a first-round bye at the Cincinnati Open before falling 2-6, 6-4, 6-4 to Thiago Agustín Tirante in the second round. Disappointed with the result, Djokovic hinted that this may very well have been his final campaign in Cincinnati when asked if he would return to the tournament.

“I certainly hope so, but unfortunately, at this point it seems more likely that I won’t,” he said in the post-match press conference. “However, we’ll see what the future holds.”

While the result already is very demoralizing for Djokovic, what was more concerning was how he crumbled under the Cincinnati heat. Notably, the temperature rose to 31°C in Cincinnati on Saturday, August 15. After taking the first set comfortably, the 39-year-old started struggling physically in the second. He even appeared to vomit during a changeover, bending over a towel as a trainer and physio rushed to his side.

Things would get worse for Djokovic later in the set, as it was evident that he wasn’t able to handle the intense heat. He removed his shirt, pressed an ice pack on his head, and even used an inhaler. Despite using various methods to counter the heat, Djokovic still wasn’t able to clinch the second set as Tirante levelled the match.

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With the set level at 1-1, Djokovic and Tirante battled through the heat for 17 minutes and 51 seconds in the third game. The game stretched through nine deuces as Djokovic gave away three game points, but also erased four break points. It turned into the longest single game played at an ATP Masters 1000 event this season.

The Serb eventually escaped when Tirante’s forehand went way over the baseline. But this game pretty much drained the remaining energy left in Djokovic as Tirante soon gained his second break of the match and clinched the third set to complete a memorable victory.

This result saw Tirante become just the second player ranked outside the top 30 to defeat Djokovic in Cincinnati. Additionally, he became just the 14th player in 20 years to come back from a set down against the 24-time Grand Slam champion.

After the match, concerns over Djokovic’s physical condition intensified when he revealed that an ongoing health condition has made it difficult for him to cope with extreme heat and humidity.

“No, it’s simply a health problem I have. It’s been bothering me for the last few years. I have a lot of problems, especially when the humidity and heat are high,” he further said in the press conference.

With his campaign in Cincinnati coming to an early end, Djokovic hasn’t been able to get substantial match practice on hard courts ahead of the US Open, which commences on August 30. But his challenge at Flushing Meadows will begin in the fan week, as he will be participating in the mixed doubles draw alongside Aryna Sabalenka.

Having reached the semifinals in the last edition of the Grand Slam, an early exit will see him lose a massive number of points in the rankings. It remains to be seen whether Djokovic will manage to make a deep run at the upcoming US Open.