Ferrer's next opponent at the grass court tournament is fellow Spaniard Ivan Navarro, who upset last year's losing finalist Marc Gicquel.
"Fans cheered me more than they did on Oscar,'' Ferrer said. "Oscar made me run a lot but running is also part of my game.''
German qualifier Benjamin Becker, who ousted top-seeded Fernando Verdasco on Tuesday, will play 2004 champion Michael Llodra in the last eight.
Fourth-seeded Rainer Schuettler, also of Germany, advanced to the quarterfinals by beating Thiemo de Bakker of the Netherlands 6-3, 7-6 (3). Schuettler next plays seventh-seeded Jeremy Chardy of France.
Raemon Sluiter, the Netherlands' only remaining contender, will play Dudi Sela of Israel in the quarterfinals after his second round opponent Marcos Baghdatis retired citing a knee injury at 4-3 in the first set.
In the women's draw, sixth-seeded Daniela Hantuchova of Slovakia advanced to the quarterfinal after beating Ukraine's Kateryna Bondarenko, 2-6, 6-2, 6-1. On a bad day for the Bondarenko sisters, Alona Bondarenko crashed out after losing 4-6, 7-5, 6-3 to fifth-seeded Francesca Schiavone of Italy. Schiavone, next meets Olga Govortsova of Belarus, who defeated Nathalie Dechy of France 6-1, 6-3.
"I had a slow start,'' Hantuchova said. "I had to focus more on my own game. When I finally managed to do that, I could turn the match around.''
Hantuchova will play Dinara Safina in the quarterfinals after the top-seeded Russian won 6-3, 6-3 against Yaroslava Shvedova of Kazakhstan.
Also, in the women's quarterfinals, it's third-seeded Flavia Pennetta vs. Tamarine Tanasugarn and Kristina Barrois vs. Yanina Wickmayer.
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