Naomi Osaka is already the second highest-paid woman in sport, second only to Serena Williams

• Naomi Osaka earned a total of $24.3 million over the last year, according to a recent Forbes list of The Highest-Paid Female Athletes 2019.
• The Japanese star won both the U.S and Australian Opens to take home $8.3 million in prize money alone.
• However her sponsorship deals with Mastercard, All Nippon Airways, Nissan and Procter & Gamble pocketed her an extra $16.0 million.
• Serena Williams is the only female athlete in the world to have earned more over the last 12 months, taking home $29.2 million.
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Double Grand Slam winner Naomi Osaka is the second highest-paid female athlete in the world over the last year having already earned an astonishing $24.3 million, according to Forbes.

The 21-year-old propelled herself into the limelight last year when she upset Serena Williams in the final of the U.S Open to win her first ever major.

She shocked the tennis world again when she won her second straight slam at the Australian Open in January, cementing her status as the sport's next superstar.

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Osaka's wins in New York and Melbourne, as well as her other exploits over the last year, have pocketed the Japanese star total of $8.3 million in prize money alone, according to Forbes' recent list of The Highest-Paid Female Athletes 2019.

Although she has struggled on the court in recent months - her first round Wimbledon exit at the hands of Yulia Patients was a career low point - Osaka's off-court earnings have kept the money rolling in.

Deals with Mastercard, All Nippon Airways, Nissan and Procter & Gamble saw Osaka earn an estimated $16 million for the 12 months to June 1, and that figure is only is only expected to increase next year after she signed a multimillion-dollar deal with Nike in April.

Altogether, her earnings both on and off the court over the last year amount to a lofty $24.3 million, Forbes has calculated.

The only female athlete in the world to earn more was Serena Williams, whose deals with brands like Nike, Beats, Gatorade and JPMorgan Chase amongst others, as well as $4.2 million in prize money, saw the 23-time Grand Slam champ earn a total of $29.2 million.

Osaka is next in action on Wednesday, when she takes on German Tatjana Maria in the Round of 32 at the Canadian Open.