Gauff, Sabalenka, Rybakina, and Pegula secure wins in Berlin as Vondrousova stumbles
As Coco Gauff opened her grass court campaign with a win over Ekaterina Alexandrova at the ecotrans Ladies Open in Berlin on Thursday, Marketa Vondrousova slipped on the grass against Anna Kalinskaya and was forced to retire injured, putting her title defense at Wimbledon in jeopardy. Aryna Sabalenka, Elena Rybakina, and Jessica Pegula all safely…