Robredo will face fourth-seeded Dmitry Tursunov, who rallied to overcome qualifier James Auckland 3-6, 6-3, 6-4.

Stefan Koubek, ranked No. 118, upset second-seeded Mario Ancic 3-6, 6-3, 6-4. The left-handed Koubek rallied past the 11th-ranked Ancic, who reached the final of the China Open two weeks ago after a two-month injury layoff.

Koubek will meet third-seeded Tomas Berdych, who defeated Bjorn Phau 6-3, 7-5.

Koubek drew even by breaking serve in the sixth and 10th games of the second set. In the deciding third set, Ancic trailed 2-5 when he saved two match points to hold serve before Koubek served out the set.

``Mario didn't come to the net often because he knew that I play the passing (shot) well,'' said Koubek, who ranked in the top 20 six years ago.