World number one Rafael Nadal saw off Jarkko Nieminen on Thursday to secure his place in the Mutua Madrid Open quarter-finals.

The Spaniard, the defending champion, came through 6-1 6-4 in third-round encounter with Finn Nieminen, letting slip a 3-1 lead in the second set and saving a break point in the ninth game before claiming victory.

Nadal, who arrived at this tournament with considerable doubts hanging over his clay dominance, said: "During the first hour I played better than yesterday (when he beat Juan Monaco), more dynamically and with more intensity.

"I knew what I was doing with every ball with no surprises. I was defending properly and knowing what was happening in every single moment. Perhaps that's something I wasn't able to do in recent weeks.

"The negative thing is in the match I had an opportunity to close it out with great feelings and I made a few mistakes in a row. That made the match more complicated. I gave the opportunity to Jarkko to play more aggressive and with more determination."

The win set up a meeting in the last eight with Czech sixth seed Tomas Berdych, a 3-6 6-3 6-2 victor over Bulgaria's twelfth seed Grigor Dimitrov.

Other seeds dropped out in the shape of Andy Murray (seventh), Milos Raonic (eighth) and John Isner (ninth), beaten by world number 46 Santiago Giraldo, Kei Nishikori (10th) and David Ferrer (fifth) respectively.

Giraldo faces Ricardo Bautista Agut, who defeated Lukasz Kubot, in the quarters, while Nishikori meets Feliciano Lopez, through after his third-round opponent Dominic Thiem retired. Ferrer takes on Ernests Gulbis, conqueror of Marin Cilic.

In the women's competition, Serena Williams, looking to be crowned champion for a third straight year, made safe progression to the quarter-finals by beating Carla Suarez Navarro 6-2 6-3.

Her next opponent is Petra Kvitova, who got past Lucie Safarova.
Li Na and Maria Sharapova will battle for a semi-final spot after their wins against Sloane Stephens and Samantha Stosur respectively, while Agnieszka Radwanska's reward for beating Roberta Vinci is a clash with Caroline Garcia, victorious over Sara Errani.

The other quarter-final pits Simona Halep against Ana Ivanovic. Halep beat Sabine Lisicki while Ivanovic got the better of Anastasia Pavlyuchenkova.