Croatian top seed Ivan Ljubicic efficiently disposed of American Kevin Kim 6-3, 6-4 to take his place in the quarter-finals of the China Open on a windy Thursday evening in Beijing [Images].

Second seeded Russian Nikolay Davydenko, the world number five, recovered from a poor start to join him in the last eight with a 7-6, 6-2 victory over erratic Slovenian qualifier Luka Gregorc.

What the shaven-headed Ljubicic lacks in flamboyance, he makes up for in tactical acumen and he just bided his time as Kim showed glimpses of his best game with some fine passing shots.

A break for a 5-3 lead was enough to give the world number three the first set while another early in the second put him on the path to an appointment with Lee Hyung-Taik.

"I served well but my baseline play was not at its best," said Ljubicic. "But I put pressure on my opponent and made him make mistakes which helped me to win the game."

Davydenko secured a 17th win in his last 20 matches despite being broken in the first game, getting back on terms five games later when Gregorc twice double-faulted and coming up with two big serves to snuff out another break chance in game seven.

The 21-year-old Slovenian's serve was good enough to bridge the chasm of 476 ranking places between the two players and take the set to a tie break but Davydenko won it easily 7-2.

In the second set Davydenko sat back on the baseline and watched Gregorc's game fall apart, sealing the win with another unreturnable serve to set up a clash with sixth seeded Thai Paradorn Srichaphan [Images], who thrashed Japan's [Images] Satoshi Iwabuchi 6-3, 6-1.

"Today the two sets were totally different," Davydenko said. "This guy was playing crazy, sometimes he was playing well and sometimes he was double-faulting, I never knew what to expect.

"The wind was tough and on my side I concentrated on not mistaking mistakes."

Eighth seeded Lee was pushed to his limits by Germany's [Images] Michael Berrer in the opening match of the day on Centre Court, finally securing his passage to the last eight 4-6, 7-6, 7-6.

The match went down to the third set tie break, when the 30-year-old South Korean won seven points in a row to recover a 4-0 deficit and set up the meeting with Ljubicic.

"Before every match I tell myself, 'It'll be a long match, but I'll still do my best'," Lee told reporters. "In the final tie break I told myself, don't give up, I should win."

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