US Open champion Naomi Osaka signed a three-year endorsement deal Thursday with Japanese carmaker Nissan, according to Business Insider.

The Japanese-Haitian tennis player had been relatively unknown before she lifted her first Grand Slam title this month against veteran Serena Williams. The match became infamous for Williams’ fiery comments toward the presiding umpire. However, several onlookers commented on Osaka’s composure despite the unraveling controversy.

“With a combination of grit and grace, Naomi Osaka is not afraid to take on the best tennis players of our time, and win, Asako Hoshino, senior vice president at Nissan, said in a statement.

Osaka, the first Japanese player to win a Grand Slam Singles tournament, spoke about the honor of becoming an ambassador for the country’s car manufacturer. “I’m so honored to represent Japan and Nissan on the world stage. I was drawn to partner with Nissan because of its strong Japanese DNA and global competitive spirit.”

Although the money involved in this contract was not announced, the deal comes a week after Osaka’s rumored $8.5 million partnership with adidas, the biggest endorsement deal of any female athlete at the apparel company.

Other sponsors of the 20-year-old include Citizen Watch Co.; Nissin Foods Holdings Co., a Japanese noodle manufacturer; and Wowow Inc., a private satellite broadcasting and premium satellite television in Japan.