World No 3 Alexander Zverev said he was playing "terrible tennis" after he was knocked out of the Shanghai Masters by France's Arthur Rinderknech 4-6, 6-3, 6-2 on Monday.
His exit leaves Novak Djokovic as the tournament's top-ranked player, increasing the 38-year-old Serb's chances of winning a record-extending fifth title in the Chinese financial hub.
Record breaking season 💪
— Tennis TV (@TennisTV) October 6, 2025
Arthur Rinderknech stuns Zverev 4-6 6-3 6-2 to earn his 23rd win of the season, making it his most successful season to date #RolexShanghaiMasters pic.twitter.com/gRt6zFh8Hw
In stifling conditions, the 54th-ranked Rinderknech came back from a set down to stun an increasingly rattled Zverev into submission.
It is the second time the Frenchman has beaten him, after bundling him out of Wimbledon earlier this year.
A despondent Zverev told reporters the match had been "nothing unusual for me, unfortunately, these days".
"Just no confidence, no belief in the shots... My year has been terrible, I'm just playing terrible tennis all round," he said, visibly emotional.
The German had injured his big toe towards the end of his last match in Shanghai but on Monday showed no sign of discomfort as he broke Rinderknech in the third game with a forehand.
He nearly went ahead early in the second set, but Rinderknech recovered his composure and broke in the fourth game.
"I'm not very sure (how I managed to turn the game around)," he said.
"I fought like hell, tried everything. (Zverev) is such a good player... I knew it was going to be a battle.
"Starting in the second set... I was able to be offensive at the right moment, in a smarter way," he said.
Keeping up the momentum, in the third set the 30-year-old broke in the third game.
Zverev had to pause to change his shoes because sweat was pouring out of them, as spectators wafted fans and wore cool packs on their foreheads to counter the suffocating humidity.
But switching footwear was not enough to save the German, and a double fault in the seventh game led to Rinderknech breaking again.
Holding with an ace to win, the Frenchman lolled his body in delighted disbelief, then danced around the court in glee.
TOP SEEDS VANQUISHED
Zverev's loss means world No 5 Djokovic now leads ranking-wise as the tournament heads into the last 16, with the 24-time Grand Slam winner facing Spain's Jaume Munar on Tuesday.
On Sunday the competition lost both defending champion Jannik Sinner, who was forced to retire with extreme leg cramps, and fourth-ranked Taylor Fritz.
World No 1 Carlos Alcaraz withdrew at the last minute to rest.
Alex de Minaur is the next highest seed after Djokovic through to the fourth round, comfortably getting past Poland's Kamil Majchrzak 6-1, 7-5.
The Australian will next meet Portugal's Nuno Borges, who put an end to the hopes of home favourite Shang Juncheng 7-6 (7/5), 4-6, 6-3.
Daniil Medvedev, the 2019 Shanghai champion, is through too, after beating Spain's Alejandro Davidovich Fokina 6-3, 7-6 (7/5).
"I haven't had a title since two years, so (I'm) not a favourite yet, but I will take it match by match, and I'm happy with the way I play so far," he told AFP.
The Russian broke early to take the first set, before edging a sweat-soaked tiebreak in the second.
Medvedev said he relished the conditions.
"Whenever it's above 28 and humid, I suffer and many players don't. Here everyone suffers," he grinned.
He will once again take on US teenager Learner Tien, who defeated him last week in the China Open semifinal.
The 19-year-old beat Britain's Cameron Norrie 7-6 (7/4), 6-3 to make the last 16 on Monday.