MADRID, May 10 (Xinhua) -- Rafael Nadal remains unstoppable on his favorite clay surface, entering the quarterfinals of the Mutua Madrid Open with a 6-3, 6-4 win over 13th seed Diego Schwartzman on Thursday.

Nadal has now won 51 consecutive sets on the surface and after his win in an hour and 43 minutes.

He will play 5th seed Dominic Thiem on Friday in the last 8.

British number one, Kyle Edmund, beat number eight seed David Goffin 6-3, 6-3 to move into the quarterfinals.

The world ranked number 22 needed just 72 minutes to book his first ever quarter-final appearance in a Masters Series event and he will now face Denis Shapovalov, who beat Milos Raonic on his way into the last eight.

The fourth seed Juan Martin del Porto fell in the last 16 after losing a tense three-set battle 3-6, 6-4, 7-6(6) to the unseeded Croatian, Dusan Lajovic.

But the sixth seed, Kevin Anderson remains in the tournament thanks to a 6-3, 7-6(7) win over German Phillip Kohlschrieber, as do No. 2 seed, Alexander Zverev after a 5-2, 6-4 win over Leonardo Mayer.

Women's top seed, Simona Halep is out of the tournament after suffering her first defeat in Madrid for three years as she was beaten 6-4, 6-3 to sixth seed Karolina Pliskova, who has now put together a nine match winning run on clay to reach the semifinals in Madrid.

France's 7th seed, Caroline Garcia also reached the last four after a 6-2, 6-3 over Carla Suarez Navarro, who Kiki Bertens, who on Wednesday beat No. 2 seed Caroline Woznianki, followed that up with a brave fight back to beat Maria Sharapova 4-6, 6-2, 6-3.