After four days without a hint of an upset, Asians Lee Hyung-Taik and Paradorn Srichaphan [Images] reached the last four of the China Open at the expense of top seeds Ivan Ljubicic and Nikolay Davydenko on Friday.

South Korea's Lee beat world number three Ljubicic 6-3, 7-6, while sixth seeded Thai Paradorn went through to the last four when Davydenko retired with an injured shoulder and a "loss of concentration" at 6-2, 2-0 down in the final match of the evening.

The Russian second seed's busy schedule finally caught up with him in his 27th tournament of the season and he left Paradorn to face third-seeded Cypriot Marcos Baghdatis, a 6-2, 6-1 winner over Thai Danai Udomchoke, for a place in Sunday's final.

Lee, the eighth seed, had Ljubicic's errors, a fierce defence of his own serve and a fortunate net cord to thank for a place in the semi-finals of the $500,000 tournament against another Croatian, fourth seed Mario Ancic.

"I never thought I would win this match until the end, that's why I'm so satisfied with the victory," Lee, ranked 60 places below Ljubicic, told reporters.

"I only made it back inside the top 100 a couple of months ago, that's why I am so relaxed and can enjoy the game.

"I felt very comfortable playing in Asia, and that was part of the reason I won."

Lee certainly looked relaxed in the opening set when he broke the Ljubicic serve at the first attempt and resisted the Croatian's attempts to break back through eight deuces in game six.

The second set was going with serve until a Lee forehand caught the net cord and looped past a stranded Ljubicic, landing well inside the line in the backcourt to give the South Korean a 6-5 lead.

With defeat looming, Ljubicic threw caution to the wind and broke back immediately but Lee held his ground to claim the tie break 7-3 and reach his first ATP semi-final of the season.

"In the second set I had break chances but he played really well," said Ljubicic, who added he had geared his training towards peaking for the weekend. "I think if he plays like this all the time, it's going to be difficult to beat him."

Ancic, returning from a two-month injury layoff, was on the back foot for the best part of two sets but still ran out a 2-6, 7-6, 6-4 winner over Slovakia's fifth seed Dominik Hrbaty.

Hrbaty dominated the first set and Ancic had his back to wall to defend his serve in the second until he suddenly found his range in the tie break.

Two successful hawkeye challenges helped him bounce back from 30-0 down to break his 28th ranked opponent for a 4-3 lead in the third set and he took the match with his 12th ace.

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