Second-seeded American James Blake eased through to the semi-finals of the Los Angeles Classic on Friday, but former world number one Marat Safin [Images] was knocked out by South Korea's Lee Hyung-taik.

Blake, hunting his first ATP title in six months, ended a run of five successive losses to compatriot Vince Spadea with a polished 7-6, 6-4 victory in sapping heat at the Los Angeles Tennis Center.

The 27-year-old New Yorker edged the opening set 7-2 on a tiebreak and broke his opponent in the first and seventh games of the second before sealing the win in one hour and 22 minutes.

Blake, who beat Spain's Carlos Moya [Images] in the Sydney International final in early January to clinch his ninth ATP title, was especially delighted to gain a measure of revenge against Spadea.

"It's definitely an emotional win beating a guy who has had that kind of success against you," a smiling Blake told reporters.

"I knew what kind of game he was going to play and I wasn't going to let it get me. Winning today was a really good feeling."

Blake, who ended last year as the American number one and ranked in the world's top five, has always relished playing the U.S. hardcourt summer stretch.

"I feel so comfortable moving on these courts that I feel like it's tough for guys to get the ball by me and I think my forehand is big enough to get it by most of these guys," he said.

LEAD SQUANDERED

Blake, who squandered a 5-3 lead in the final set before holding off Spadea, will meet seventh-seeded Lee in the last four, the Korean having come from behind to upset Safin 4-6, 7-5, 6-4.

The big-serving Russian appeared to have a fluctuating match under control when he broke Lee in the opening game of the final set before leading 4-2.

But the Korean broke back in the eighth before sealing victory in the 10th when Safin double-faulted on match point.

"I had an opportunity to get a double-break but just missed it by a little bit," third-seeded Safin said, referring to his chance to lead 5-2 in the decider.

"But I went for it and all of a sudden he broke me out of nowhere. He was more aggressive, I was more passive. He was more confident and my confidence level dropped."

Wildcard Nicolas Kiefer, inching his way back into form after a long injury layoff, beat fellow-German Michael Berrer 7-6, 6-1 in an earlier match.

The 30-year-old Kiefer, who hurt his wrist at last year's French Open, won the opening set 7-5 on a tiebreak before storming through the second set with three breaks of serve.

Kiefer will meet Czech Radek Stepanek in the last four after the former world number eight dusted off local favourite Zack Fleishman 6-4, 6-2 in 62 minutes in their quarter-final.

The Czech needed a single break to clinch the first and broke in the opening game of the second before easing to his second consecutive ATP semi after reaching the last four in Gstaad, Switzerland [Images] earlier in the month.

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