Naomi Osaka knows the secret to her meteoric rise to the tennis summit was her ability to enjoy herself on court and, by the same token, that her current slump has drained every bit of fun out of her game.

Her first-round Wimbledon exit to Kazakhstan’s Yulia Putintseva on Monday was the tournament’s first major shock and she was left close to tears in an emotional news conference as she tried to put into words how her form has deserted her.

Having thrust herself into the limelight by winning back-to-back Grand Slam titles at the U.S. and Australian Opens, the pressure and scrutiny that come with being among the sport’s biggest stars has seemingly taken its toll on the 21-year-old.

At times in her 7-6(4) 6-2 defeat, the second seed looked visibly despondent as the attacking game that had taken her to world number one delivered little more than a flurry of unforced errors.

The weapons that had been so potent in New York and Melbourne were wayward and scattergun on Centre Court and as the match swiftly got away from her in the second set, Osaka looked increasingly forlorn.

When she was asked by reporters if her new-found fame had been difficult to get used to, she cut the conversation short.

“Can I leave? I feel like I’m about to cry,” she said.

Having only reached one semi-final since lifting the Australian Open trophy in January, the coming weeks will lead to head-scratching analysis from Osaka as she tries to rediscover the missing ingredients from her game.

“The key for me was just, like, having fun, I guess, like learning how to have fun, kind of taking pressure off myself. I hope I can somehow find a way to do that,” she said.

After her third-round exit at the French Open, which ended her run of Grand Slam success and was closely followed by her losing the top ranking, she said a weight of expectation had been lifted off her shoulders.

Yet there was little evidence on Monday that she was playing with a new-found freedom.

Osaka began brightly, breaking in the third game, but that was as good as it got for the Japanese.

Her opponent leveled at 3-3 and took the first set on a tiebreak, before turning the screw decisively in the second.

Osaka smacked the ball into the turf in frustration in the first game as she gave up two break points and while she escaped from that, she was broken four games later and again to trail 5-2.

Putintseva quickly brought up two match points on her own serve and after spurning the first, put Osaka out of her evident misery on the second when the Japanese sliced a backhand into the net.