- After winning back-to-back Grand Slam events, Osaka was on top of the tennis world and signing multi-million dollar endorsement deals.
- BBC tennis analyst and former three-time Wimbledon winner John McEnroe suggested sponsorship obligations may have distracted her from her full-time job playing tennis.
- Former 18-time Grand Slam champion Chris Evert recently told us clay and grass isn't Osaka's favored surface anyway.
- Last week, Evert called for patience with Osaka. "She's still young and she has the game to go all the way."
- Visit Business Insider's home page for more stories .
Naomi Osaka was eliminated from the Wimbledon Championships on Monday, losing to Yulia Putintseva in the first round.
For Osaka, a back-to-back Grand Slam champion, it is the latest humiliating misstep after a sudden fall from world number one status.
Putintseva's strategy was played perfectly as she manipulated her opponent's nerves, duped Osaka with drop shots, and kept the 21-year-old guessing with a variety of shot-making. In total, Osaka hit 38 unforced errors.
After the win, Putintseva's third straight triumph over Osaka, the 24-year-old Kazakh told the BBC that every year she's "feeling better on grass." Osaka, in contrast, asked to leave the post-match press conference as she felt she was about to cry.
How long has this been going on?
Osaka won back-to-back majors when she famously beat Serena Williams in the US Open final last year, then Petra Kvitova in the Australian Open final in January.
Weeks later, she split from her coach Sascha Bajin , who guided her from world no. 68 to the two Grand Slam titles, which was described by The Guardian journalist Kevin Mitchell as a sign of her "steeliness."
But in her first match without Bajin, Osaka made errors and failed to build momentum in the first round of the Dubai Tennis Championships. Kristina Mladenovic, an unseeded French player, beat her in straight sets 6-3, 6-3.
Since then, Osaka has been beaten by unseeded players in the Madrid Open, French Open, Birmingham Classic, and now Wimbledon.
Why is this going on?
When Osaka was world no.1 earlier in the year, it was clear she had the physical attributes to fend off challenges from the sport's biggest names and claim championship trophies.
She doesn't look like she's all there right now.
But the BBC tennis analyst and former three-time Wimbledon winner John McEnroe believes Osaka's mentality right now is far from optimal. "To me it's mental," he said shortly after her loss.
"You need that intensity. You've got to be on it, especially early in the tournament.
"Obviously, she needs to work on her volley and you need to be able to move forward more successfully, but to me she just doesn't look like she's all there right now."
Shortly after winning the US Open last year, Osaka signed a three-year endorsement deal with the Japanese automobile firm Nissan, as well as a mega-contract with Adidas. Another of her sponsors, Yonex, experienced a 10% rise in stock value as a result of her on-court success . That effect is rare in sports, and invited comparisons to Cristiano Ronaldo, who spiked the value of Juventus FC shares when he first joined the Italian club last summer.
McEnroe suggested it is things like this that may have "distracted" Osaka from her main job, playing tennis, because "she's probably got a lot of offers, opportunities," away from the court. "It just seems like she's lost her confidence," he said. "And that's amazing considering where she was three or four months ago."
Where will she be three or four months from now?
Form, in Osaka's case, may only be temporary as her class could shine through once again, albeit on a hard court later in the year.
The grass season concludes this month before big events like the Canadian Open and Cincinnati Open take center stage. Osaka will then defend her US Open title in New York in late August and early September.
18-time Grand Slam champion Chris Evert told Business Insider at the Dubai Duty Free WTA Summer Party in London last week that Osaka "did okay in the hard court season" but then "went to clay and that is not her surface."
She added: "Now she's on grass and she hasn't really had a lot of success on grass."
Osaka is only 21 and still developing as a tennis player and an athlete in general. "There's a few adjustments when you reach number one," Evert said. "She's still young and she has the game to go all the way, but it might take a little more time."
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