US Open defending champ loses to 19-year-old in first round
US Open women's singles defending champion Angelique Kerber lost to Japan's 19-year-old Naomi Osaka in the first round on Tuesday. The 45th-ranked Japanese took 79 minutes to oust the world number six in straight sets. Meanwhile, women's singles world number one Karolina Pliskova advanced to the second round of the tournament after a straight set win over Magda Linette.