Former world number-one women's tennis player Kim Clijsters of Belgium has reached the quarterfinals of the J&S Cup clay-court tennis tournament in Warsaw, Poland.

Clijsters, the seventh seed, extended her winning streak to 16 with a straight-sets win over Russian Maria Kirilenko, 6-2, 6-1. The Belgian is playing in her fourth tournament this year after spending much of last year sidelined with a wrist injury. She is coming off tournament wins in California and Florida.

Also Wednesday, eighth-seeded Italian Silvia Farina-Elia made the final eight with a straight-set win over Czech qualifier Zuzana Ondraskova 6-1, 6-2.

The clay-court tournament is one of several events players are using to prepare for the second major tournament of the year, the French Open, which starts May 23 in Paris.

Some information for this report provided by Reuters.