Spain's Garbine Muguruza makes a forehand return to Shelby Rogers of the U.S. during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Lee Jin-man)

Spain's Garbine Muguruza makes a forehand return to Shelby Rogers of the U.S. during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Lee Jin-man)

Germany's Laura Siegemund serves to Coco Vandeweghe of the U.S. during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Andy Brownbill)

Spain's Garbine Muguruza makes a backhand return to Shelby Rogers of the U.S. during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Lee Jin-man)

Coco Vandeweghe U.S. makes a backhand return to Germany's Laura Siegemund during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Andy Brownbill)

Shelby Rogers of the U.S. makes a backhand return to Spain's Garbine Muguruza during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Lee Jin-man)

Shelby Rogers of the U.S. makes a backhand return to Spain's Garbine Muguruza during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Lee Jin-man)

Shelby Rogers of the U.S. makes a backhand return to Spain's Garbine Muguruza during their first round singles match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Lee Jin-man)

Amanda Anisimova of the U.S. reacts during her first round match against Zarina Diyas of Kazakhstan at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Andy Brownbill)

Amanda Anisimova of the U.S. makes a backhand return to Zarina Diyas of Kazakhstan at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan. 21, 2020. (AP Photo/Andy Brownbill)