Switzerland's Roger Federer gives the thumbs up as he leaves the court after winning his quarter-final against Croatia's Mario Ancic yesterday. - AP

WIMBLEDON, England (AP):

FIVE-TIME champion Roger Federer outclassed Mario Ancic, the last man to beat him at Wimbledon, in straight sets yesterday to reach the semi-finals and extend his grasscourt winning streak to 64 matches on the first day of significant rain delays at the All England Club.

Riding his dominant serve and punishing forehand, Federer put on a masterful performance to beat Ancic 6-1, 7-5, 6-4 and move another step closer to becoming the second man in history to win Wimbledon six years in a row.

Federer served 15 aces, and finished with three straight in the final game - including a second serve on match point. He won 61 of 71 points on serve, including his last 16, for his 39th straight win at Wimbledon.

"I'm playing great, serving excellent," said Federer, who hasn't dropped a set all tournament. "Many aces is always helpful. Some rain delays broke my momentum a little bit. I got back into the match and played really well all the way through."

Russian in semi-final

Federer will next face Marat Safin, who served 18 aces and overcame Feliciano Lopez 3-6, 7-5, 7-6 (1), 6-3 to become the first Russian man to make the Wimbledon semi-finals in the 40-year history of the Open era.

In the bottom half of the draw, number two Rafael Nadal edged closer to a third consecutive Wimbledon final against Federer by blowing away Britain's Andy Murray 6-3, 6-2, 6-4.

"I played probably my best match for sure here," said the four-time French Open champion, who didn't face a break point and, like Federer, hasn't been broken in five matches.

Nadal, bidding to become the first man to win the French Open and Wimbledon in the same year since Bjorn Borg in 1980, will have to wait an extra day to find out who he will face in the semi-finals.

The quarter-final between 94th-ranked Rainer Schuettler and number-45 Arnaud Clement was suspended at one set apiece because of fading light.

Schuettler won the first 6-3 and Clement took the second 7-5.

Federer was at his vintage best, holding serve at ease and gliding across the court and ripping shots that flew past Ancic or forced him into errors. He has reached the semi-finals for the 17th consecutive time at a Grand Slam event.

"I really feel like I'm playing as good as the last few years," the 12-time Slam champion said. "I'm on such a great winning streak on grass. I feel so comfortable on Centre Court. My confidence level is really high."

Rocky start

Safin, a former top-ranked player who won the 2000 US Open and 2005 Australian Open, has slipped steadily in the rankings over the past three years and came into the tournament at number 75.

The Russian got off to a rocky start against the left-handed Lopez, and was down 5-2 in the first set when play was suspended by rain.

Even though he ended up losing the set, Safin stepped up his game after the break and took command. Lopez double-faulted on set point in the third-set tiebreaker and served his sixth double-fault on match point.

"I was too nervous to play well in the beginning," Safin said. "I got a service break and played better. I had to calm down. I was too nervous to make anything happen."

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