Samantha Stosur defeats Svetlana Kuznetsova to reach 2nd round of Western & Southern Open

Former U.S. Open champion Sam Stosur moved into the second round of the Western & Southern Open with a 6-1, 7-5 win over Svetlana Kuznetsova on Monday.

Stosur, who won the 2011 U.S. Open, lost in the round of 16 at the Rogers Cup in Toronto last week. She won the Southern California Open the previous week.

In other first-round women's matches, wild card Lauren Davis upset No. 34 Klara Zakopalova, 7-6 (3), 7-6 (1), while 25th-ranked Simona Halep rallied to defeat Su-Wei Hsieh 6-7 (5), 6-1, 6-2.

In early first-round men's action, American Mardy Fish lost to 26th-ranked Philipp Kohlschreiber 7-5, 6-2.

American Brian Baker — in his first match since suffering a right knee injury in the first round of the Australian Open — pulled off 7-5, 6-3 upset of No. 63 Denis Istomin.