Serena Williams exited the Western & Southern Open in Cincinnati after a gruelling second-round defeat to Petra Kvitova. Number eight seed Kvitova applied the pressure from the start, breaking 23-time grand slam winner Williams twice in the first set. A nervy start to the third set saw both players drop their serve, but Kvitova found her stride to go 4-2 up and eventually win 6-3, 2-6, 6-3.

Azarenka out, Svitolina wins
Meanwhile, No. 6 seed Caroline Garcia fought back from 2-0 down in the first set and 5-3 in the second to overcome Victoria Azarenka 6-4, 7-5. Fifth seed Elina Svitolina faced an equally tough match against Svetlana Kuznetsova, with the Russian threatening Svitolina's lead in each set. With the breaks going back and forth, the Ukrainian eventually held serve to seal a 7-6 (7/1), 4-6, 6-4 victory.