Aryna Sabalenka of Belarus celebrates victory with on-court presenter Jelena Dokic, following her first round match against Sloane Stephens of the U.S. at the Australian Open tennis championship in Melbourne, Australia.

Aryna Sabalenka, left, of Belarus is congratulated by Sloane Stephens of the U.S. following their first round match at the Australian Open tennis championship in Melbourne, Australia.

A young fan holds a poster for Aryna Sabalenka of Belarus after she defeated Sloane Stephens of the U.S. in their first round match at the Australian Open tennis championship in Melbourne, Australia.

Sloane Stephens of the U.S. plays a backhand return to Aryna Sabalenka of Belarus during their first round match at the Australian Open tennis championship in Melbourne, Australia.

Aryna Sabalenka of Belarus plays a forehand return to Sloane Stephens of the U.S. during their first round match at the Australian Open tennis championship in Melbourne, Australia.

Sloane Stephens of the U.S. plays a forehand return to Aryna Sabalenka of Belarus during their first round match at the Australian Open tennis championship in Melbourne, Australia.

Aryna Sabalenka of Belarus waves as she walks onto Rod Laver Arena ahead of her first round match against Sloane Stephens of the U.S. at the Australian Open tennis championship in Melbourne, Australia.

Sloane Stephens of the U.S. waves as she walks onto Rod Laver Arena ahead of her first round match against Aryna Sabalenka of Belarus at the Australian Open tennis championship in Melbourne, Australia.