Petkovic (Indian Wells), No.9 Muguruza (Toronto), to No.8 Karolina Pliskova (New Haven) and No.6 Safarova (US open).
Petkovic (Indian Wells), No.9 Muguruza (Toronto), No.8 Karolina Pliskova (New Haven) and No.6 Safarova (US Open).