MADRID, May 9 (UPI) -- World No. 1 and defending champion Serena Williams dropped just two points on serve Thursday in grabbing a berth in the quarterfinals of the Mutua Madrid Open.
Williams needed just 64 minutes to oust 13th-seeded Maria Kirilenko 6-3, 6-1. She took an amazing 32-of-34 points on serve.
Williams had four breaks in eight receiving games and, combined with taking more than half the points off Kirilenko's serve, won 68 percent of the points in the match. Williams is 7-0 in her career versus Kirilenko.
No. 2-ranked Maris Sharapova overcame three breaks in a 6-2, 7-5 decision over Sabine Lisicki. Sharapova, however, had six breaks in Lisicki's 10 games serving.
Other third-round matches Thursday saw No. 7-seeded Sara Errani beat Varvara Lepchenko 7-5, 6-3 while Ekaterina Makarova ousted 14th-seeed Marion Bartoli 6-3, 6-2 and Kaia Kanepi advanced over Daniela Hantuchova 6-3, 6-4.
The quarterfinals have Williams playing Anna Medina Garrigues and Makarova facing Errani in one half of the draw while Sharapova meets Kanepi and sixth-seeded Angelique Kerber goes against No. 16 Ana Ivanovic in the other.