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 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 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 during the U.S. hardcourt summer season.
"I love playing on hardcourts, especially here in America where I feel my fans are always with me," he said. "It gets hot out and the ball is jumping and I feel great on these courts.
"It's where I grew up and 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."
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 the match under control when he broke Lee in the opening game of the final set but the Korean broke back in the eighth before sealing victory in the 10th when Safin double-faulted on match point.
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 either Czech Radek Stepanek or local favourite Zack Fleishman in the last four. Stepanek and American wildcard Fleishman were scheduled to play in the late match on the stadium court.