2020 U.S. Open: What to Watch on Saturday. Ruud, Casper (1998- ), Berrettini, Matteo (1996- ), Williams, Serena, Stephens, Sloane, Kenin, Sofia (1998- ), Jabeur, Ons, Tennis, United States Open (Tennis), Medvedev, Daniil (1996- ), Azarenka, Victoria, Sakkari, Maria (1995- ), De Minaur, Alex (1999- ), Khachanov, Karen (1996- )