WARSAW, Poland, May 1 (UPI) -- Former world No. 1 Martina Hingis of Switzerland was among Monday's opening-round winners at the $600,000 women's J&S Cup in Warsaw, Poland.
Hingis, a five-time Grand Slam champion, defeated Russian Maria Kirilenko 7-5, 7-6 (7-1).
Hingis, who returned to the WTA Tour as a full-time member in January following a three-year layoff, is playing her first tennis since an appearance in Miami in March.
In other first-round play, Klara Koukalova beat fellow Czech Iveta Benesova 7-6 (7-3), 6-4 and Russian Anna Chakvetadze defeated Serbian Jelena Jankovic 7-5, 6-3.
A scheduled match between ninth-seeded Slovakian Daniela Hantuchova and Israeli Anna Smashnova was postponed until Tuesday.
Justine Henin-Hardenne, who is not defending her title this week, beat Russian Svetlana Kuznetsova in last year's Warsaw final. The top seed is U.S. Open champion Kim Clijsters.
