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SHANGHAI - World number one Roger Federer reached the semi-finals of the Masters Cup overnight (NZ time) without hitting a ball, then beat Ivan Ljubicic 7-6 6-4 to bring defending champion David Nalbandian along with him.
Argentine Nalbandian improved to 1-2 for the round robin stage by downing
Andy Roddick 6-2 7-6 earlier in the day, sending Federer through and ending his American opponent's interest in the tournament.
Nalbandian was left needing a Federer victory in the second match of the evening to stay in the championship and, despite being broken in his first service game, the Swiss duly delivered.
Federer became the first player to win 90 matches in a season since Ivan Lendl won 106 in 1982, extended his winning streak to 27 matches and ensured he will remain unbeaten in Masters Cup group ties for at least another year.
Champion in 2003 and 2004 and losing finalist to Nalbandian last year, Federer said discovering he was through to the semi-finals for a fifth year in succession just before going out for the match had distracted him.
He regained his composure, however, to win the first set 7-2 in the tiebreak while a break in the third game of the second proved sufficient for the win, which he sealed with an ace after one hour and 33 minutes.
"It was very confusing in the beginning," he said. "It definitely took me a few games to kind of really get the sense that I want to win this match and I wanted to keep this great streak I have going and everything.
"So there was plenty of reasons. I'm happy I came through, especially convincingly. Gives me confidence for the semis."
Ljubicic, who went out on set count, said it was "weird" that he was going home despite having beaten Nalbandian in their group encounter but had no complaints about his defeat to Federer.
"He's always asking me a lot," said the world number four. "I'm always pushed to the limits. I have always a lot of pressure on my serve. On my shots I always have to go for little bit more, and it's really hard to play like that the whole match."
American James Blake qualified for the last four from Gold Group on Wednesday evening, while world numbers two and three, Rafael Nadal of Spain and Russian Nikolay Davydenko, face off for the final slot in the semis on Friday.
Fifth ranked Roddick, a shadow of the player who came close to upsetting Federer on Tuesday, joins Spain's Tommy Robredo in being eliminated from the tournament.
"Give credit where credit's due, I didn't play badly tonight ... but he played very well," said Roddick. "What's done is done now. We'll look forward to next year."
Roddick also started poorly and Nalbandian pounced on his below-par serves to break in the first game of the match.
"In the beginning I played very good," said Nalbandian, who was playing despite learning of the death of his nine-year-old godson in an elevator accident back home in Cordoba.
"I was hitting good shots and got control of the match. He didn't serve so good, that's why I went away."
The second set was closer but although Roddick recovered a break when his opponent was serving for the set, it only delayed his defeat as he gave up a 3-1 lead to lose 7-4 in the tiebreak.
"Sometimes you need a little of luck," said Nalbandian of his route to the semi-finals.
- REUTERS