Aryna Sabalenka’s preparations for her US Open title defence have suffered another setback after the world number one was knocked out of the Cincinnati Open by 20-year-old Czech player Sara Bejlek.
The top seed appeared firmly in control before Bejlek produced a remarkable comeback to secure a 7-6 (9-7), 6-4 victory and reach her first WTA 1,000 quarter-final.
Sabalenka led 5-1 in the first-set tiebreak and was also 4-1 ahead in the second set, but the 35th-ranked Bejlek refused to surrender.
The Czech won six of the next seven points to take the opening set and then overturned another significant deficit in the second to complete one of the biggest victories of her career.
“I totally lost my words. I just keep believing and that was the key today,” Bejlek said after the match.
“She played amazing tennis and I was just believing, keep fighting and I was just trying my best and that’s it.”
The victory marked Bejlek’s first win against a top-10 opponent and continued an impressive season that includes her Abu Dhabi hard-court title in February, which she won as a qualifier.
She will face former Australian Open champion Madison Keys in the Cincinnati quarter-finals.
Sabalenka faces ranking pressure
The defeat also puts Sabalenka’s position at the top of the women’s rankings under immediate threat.
Elena Rybakina can overtake the Belarusian as world number one if she reaches the Cincinnati final. Rybakina faces Iga Swiatek in a highly anticipated quarter-final.
For Sabalenka, the loss adds to a difficult build-up to the US Open, which begins on August 30.
The 28-year-old is attempting to become the first woman since Serena Williams in 2014 to win three consecutive US Open titles.
However, her form heading into New York has been inconsistent. She suffered early exits in both Toronto and Cincinnati after winning the Sunshine Double at Indian Wells and Miami in March.
Since that success, Sabalenka has reached only one semi-final, losing to Jessica Pegula in Berlin.
Paul sends Zverev out
There was also a major upset in the men’s draw, where American Tommy Paul eliminated top seed Alexander Zverev in a dramatic three-set encounter.
Zverev won the opening set and led 4-3 in the second before rain forced a 90-minute suspension.
The German, who recently won the French Open, had a match point at 6-5 in the second-set tiebreak but failed to convert it.
Paul seized the opportunity, forced a deciding set and completed a 4-6, 7-6 (8-6), 6-4 victory.
Zverev led 4-2 in the final set, but world number 24 Paul produced a decisive four-game winning streak to seal the upset.
Paul advances to the quarter-finals, where he will meet Italy’s Flavio Cobolli.
