‘When I win, I don’t feel happy’: Tennis ace Osaka cries in press conference again as she reveals plan to take a break (VIDEO)

Naomi Osaka has broken down in tears in a press conference again and admitted that she does not know when she will next play tennis after losing to the world number 73 at the US Open.

The reigning champion cut a frustrated figure as she was dethroned by 18-year-old Leylah Fernandez in New York, repeatedly smashing her racket on the way to a shock defeat after winning the first set.

Two weeks after the world number three made headlines for sobbing at a media call when she was asked about balancing her high profile and dislike of media duties, the 23-year-old was again moved to tears as she admitted she does not know when she will take to a court again.

"I feel like, recently, when I win I don't feel happy," the Japanese sensation confessed. "I feel more like a relief. And then when I lose, I feel very sad – and I don't think that's normal."

Osaka told reporters she "didn't really want to cry" before a man off camera told the press that the conference was "done".

"Thank you, no – I kind of want to finish," responded Osaka. "So basically I feel like... this is very hard to articulate well.

"I feel like I'm kind of at this point where I'm trying to figure out what I want to do.

"I honestly don't know when i'm going to play my next tennis match. Sorry but I think I'm going to take a break from playing for a while."

Osaka repeatedly patted her face for comfort before holding two apologetic thumbs up to her audience.

Analyzing her third-round exit at Flushing Meadows, she suggested her sub-par performance against the Canadian was a product of off-court issues.

"I don't think it was her serve because I've been able to return pretty well against people that served better," she observed.

"I don't think it's the occasion because I've been in this situation before, so I know that... I guess we're all dealing with some stuff. I know I am."

Four-time Grand Slam champion Osaka has had an underwhelming season since winning the Australian Open in January.

Her French Open campaign ended in the second round and was marred by a row with tournament organizers after she announced a press boycott, and she was knocked out of her home Olympics in the third round.

In June, Osaka was named as the highest-earning female athlete of all time, with a net worth estimated at $60 million.