Naomi Osaka is reportedly set to sign the biggest deal Adidas has ever agreed to with a female athlete.

Osaka, a 20-year-old tennis player, just won the US Open — her first Grand Slam title. She defeated the 23-time major winner Serena Williams in straight sets, 6-2, 6-4, on Saturday at Arthur Ashe Stadium in New York, collecting a $3.8 million paycheck.

But her new deal with Adidas could dwarf her earnings from tennis, The Times reports.

Osaka is reportedly on a “six figure” salary with Adidas that will expire this year.

The Times says a contract worth an estimated $8.5 million a year will be announced Thursday. This would be Adidas’ biggest deal with a female athlete, according to Yahoo, which also says it would see the Japanese star rocket up Forbes’ list of the highest-paid women in sports.

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