Relaxed Serena through to last eight in Madrid

A laid-back Serena Williams breezed into the Madrid Open quarter-finals on Thursday when she barely broke sweat in a 6-3, 6-1 drubbing of Maria Kirilenko.

The world number one and top seed, defending champion at the premier clay event in the Spanish capital, needed just over an hour to dismiss the 13th-seeded Russian and set up a last-eight meeting with Spanish wildcard Anabel Medina Garrigues.

"I just felt really relaxed today," Williams told a news conference.

"I felt like I was just taking my time," the 31-year-old American added. "So hopefully I can keep calm and relaxed."

Williams, chasing a fourth title of the year and the 50th of her career, was joined in the quarter-finals by second seed Maria Sharapova who knocked out unseeded German Sabine Lisicki 6-2 7-5.

The Russian world number two and French Open champion will play Slovakian wildcard Daniela Hantuchova or unseeded Estonian Kaia Kanepi for a place in the last four.

Medina Garrigues, a former world number 16 now ranked 63rd, went through on Wednesday after her opponent Yaroslava Shvedova of Kazakhstan withdrew with an arm injury.

"She's definitely going to be really tough for me," Williams said of the Spaniard. "She's a grinder on clay and she's Spanish. I know a lot fans really like her here."

After her comfortable win over Lisicki, Sharapova reflected on how much she has improved on clay in recent years.

The 26-year-old's triumph at Roland Garros in 2012 made her only the sixth woman in the open era to win all four grand slam singles titles.

"It took me many years to get to the level of where I am today (on clay), it certainly didn't happen overnight," she told a news conference.

"I worked extremely hard on getting stronger and recovering better, moving better on the court, giving myself a better position on the court, especially after being on the defensive and trying to play aggressively as I always do on quicker surfaces.

"But just give myself that chance to recover. I think I've learned a lot and over the years and I've really improved."

Photograph: Gonzalo Arroyo Moreno/Getty Images