Czech Republic's Karolina Pliskova serves to United States's Sloane Stephens during their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)

United States's Sloane Stephens reacts as she plays against Czech Republic's Karolina Pliskova during their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)

United States's Sloane Stephens plays a return to Czech Republic's Karolina Pliskova during their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)

United States's Sloane Stephens plays a return to Czech Republic's Karolina Pliskova during their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)