World number one Roger Federer won his 20th match in a row over a top-10 opponent, beating Lleyton Hewitt for the fifth consecutive time to book a semifinal spot at the ATP Masters Cup.
The 23-year-old Swiss defending champion beat Hewitt 6-3, 6-4 on Wednesday in a round-robin match delayed and interrupted by rain, leveling his lifetime record against Hewitt at 7-7 in a year where he has tormented the Aussie star.
Federer previously beat Hewitt this year in the Australian Open round of 16, Wimbledon quarterfinals, US Open final and Hamburg semifinals. Federer won each of those titles on his way to 10 crowns and a 71-6 record so far this year.
"I just tried to play my game. For the moment, that's enough against him," Federer said. "Hopefully that's going to continue."
This was Hewitt's first loss to Federer this year in which he did not drop a set at love. Federer, coming off a six-week injury layoff, beat Hewitt in the US Open final 6-0, 7-6 (7/3), 6-0.
"I played a good match, obviously not as good as the US Open," Federer said. "My second match in a long time, obviously it's hard to play at that level. I had to play tough to beat him. We have had better matches."
Federer, in his first event since winning last month's Bangkok title, has shown no sign of trouble from a left thigh injury suffered in an Oct. 25 practice session in his 2-0 start at the season-ending hardcourt event.
"I always feel like I have room for improvement," Federer said.
Hewitt, who could face Federer in Sunday's final, could not capitalize on six break points in the match, which began three-and-a-half hours late and was halted for an hour in the second set with Federer ahead 4-2.
"I had a lot of chances," Hewitt said. "I had the first break points and I wasn't able to take them. Sort of been the story in the last few matches I've played against Roger. I've had the opportunities and not been able to take advantage of them."
Spain's Carlos Moya waited through an eight-hour rain delay to defeat Argentina's Gaston Gaudio 6-3, 6-4. Gaudio's title bid became undone while Moya likely must beat Federer to advance.
"I have to forget who I'm playing with, just play my match and enjoy it," Moya said. "It's not often you get to play one of the best players ever."
Moya, who lost his opener to Hewitt, captured his first victory since the second round of the US Open by beating the reigning Roland Garros champion. Moya was out from Sept. 24 until this week with a right shoulder injury.
"I thought I was going to have a day off," Federer said 18 hours before facing Moya.
Russia's Marat Safin will face American Andy Roddick to decide a semifinal spot yesterday while Britain's Tim Henman meets Argentina's Guillermo Coria, the loser being eliminated from the title picture.
Hewitt faces Gaudio today and must win to have a hope of advancing further.
"I know what I've got to do," Hewitt said. "The ball is in my court."
Federer, whose perfect run against top-10 rivals began with an unbeaten run at this event a year ago, swatted a stunning backhand crosscourt winner past Hewitt for a break to lead 3-1 and held serve from there to claim the set.
Federer, who denied Hewitt on three break points in each set, broke him to open the second set and the two exchanged holding serves until rain returned with Federer ahead 4-2.