'Sad to see': Tennis world stunned by fresh Naomi Osaka drama

Pictured here, Naomi Osaka looks upset during her Cincinnati Masters round of 16 defeat.
Naomi Osaka suffered a shock defeat in the Cincinnati Masters round of 16. Pic: Getty

World No.2 Naomi Osaka has crashed out in the round of 16 at the Cincinnati Masters in a result that has left the tennis world in shock.

The Japanese star went down 3-6, 6-3, 6-3 to No. 76 Jil Teichmann in a worrying sign ahead of the US Open.

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Osaka has had a tumultuous year that included an infamous media blackout and a break from the game to work on her mental health concerns.

The 23-year-old was reduced to tears earlier in the week after an aggressive line of questioning about her dislike of the media, before the Cincinnati tournament began.

The four-time major winner was victorious in her previous match against teen American sensation Coco Gauff, but she suffered a shock defeat to Swiss No.76 Teichmann in Cincinnati.

Osaka repeatedly punched her left thigh with her left wrist and talked loudly to herself throughout the contest, but struggled to find another gear when she needed to.

The Japanese star got off to a flying start, scoring back-to-back breaks on her way to taking out the first set.

However, Osaka's level dropped considerably in the second set and Teichmann seized on her opportunity to capitalise.

Osaka was forced to save three breakpoints and a set point before meekly surrendering her own service game to allow Teichmann to level the contest at a set apiece.

The Swiss had all the momentum going into the deciding set and Osaka was punished for a catalogue of unforced errors as Teichmann booked her spot in the quarter-finals.

The stunning upset left tennis fans in shock on social media.

Sponsor matches Naomi Osaka donation pledge

Osaka pledged to donate her entire prizemoney from the Cincinnati tournament to those affected by the recent earthquake in Haiti.

The incredible gesture has since been matched by The Western & Southern Financial Group, who sponsor the WTA event.

Four-time grand slam champion Osaka said she would donate her earnings from the tournament to the impoverished nation after it was struck by a 7.2-magnitude earthquake last weekend.

Naomi Osaka is seen here during her match against Coco Gauff at the Western & Southern Open in Cincinnati.
Naomi Osaka will donate her prizemomey from the Cincinnati Masters to Haiti earthquake victims. Pic: Getty (Dylan Buell via Getty Images)

The earthquake has killed at least 2,189 people and reduced tens of thousands of buildings to rubble.

"Really hurts to see all the devastation that's going on in Haiti, and I feel like we really can't catch a break," Osaka, who is the daughter of a Haitian father and Japanese mother, said in a tweet on Saturday.

"I'm about to play a tournament this week and I'll give all the prize money to relief efforts for Haiti. I know our ancestors blood is strong we'll keep rising."

Last year, Forbes reported Osaka was the world's highest-earning female athlete, taking in $US37.4 million (A$51.8 million) over a 12-month period in prizemoney and endorsements.

with agencies

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