U.S. Serena WILLIAMS celebrates after winning the women's singles second round of the French Open tennis tournament against Japan's Kurumi NARA at Roland Garros in Paris, France on May 30, 2019. ( The Yomiuri Shimbun via AP Images )

U.S. Serena WILLIAMS celebrates after winning the women's singles second round of the French Open tennis tournament against Japan's Kurumi NARA at Roland Garros in Paris, France on May 30, 2019. ( The Yomiuri Shimbun via AP Images )

U.S. Serena WILLIAMS celebrates after winning the women's singles second round of the French Open tennis tournament against Japan's Kurumi NARA at Roland Garros in Paris, France on May 30, 2019. ( The Yomiuri Shimbun via AP Images )

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

(190530) -- PARIS, May 30, 2019 (Xinhua) -- Victoria Azarenka of Belarus reacts during the women s singles second round match with Naomi Osaka of Japan at French Open tennis tournament 2019 at Roland Garros, in Paris, France on May 30, 2019. Victoria Azarenka lost 1-2. (Xinhua/Han Yan) (SP)FRANCE-PARIS-TENNIS-ROLAND GARROS-DAY 5 PUBLICATIONxNOTxINxCHN

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM

PARIS, FRANCE - MAY 30: Serena Williams of the USA in action against Kurumi Nara (not seen) of Japan during their second round match at the French Open tennis tournament at Roland Garros Stadium in Paris, France on May 30, 2019. Mustafa Yalcin / Anadolu Agency/ABACAPRESS.COM