Romanian second seed Simona Halep and Italy's Flavia Pennetta have advanced to a US Open semi-final match-up by ousting two-time grand slam champions Victoria Azarenka and Petra Kvitova.
Romanian second seed Simona Halep and Italy's Flavia Pennetta have advanced to a US Open semi-final match-up by ousting two-time grand slam champions Victoria Azarenka and Petra Kvitova.