Top-ranked Roger Federer saved six set points in beating fifth-seeded David Ferrer 6-3, 7-6 (14) in the Swiss Indoors quarter-finals on Friday.
Federer was broken three times in the match as he bids to win his hometown tournament for the first time. He lost in the final in 2000 and 2001.
"It was surely luck some of the time," Federer said. I had to make sure to play some good points under pressure and I did. It was a great match in the end."
World No. 1 Federer advanced to yesterday's semi-finals against Paradorn Srichaphan, who beat seventh-seeded Jose Acasuso of Argentina 7-6 (2), 6-3 for a fourth consecutive time.
Second-seeded David Nalbandian was upset by Stanislas Warinka of Switzerland 7-6 (7), 6-2, leaving Nalbandian to try at next week's Paris Masters to qualify for the elite Masters Cup. Nalbandian won the Masters Cup last year in Shanghai.
Warinka served 13 aces against the world No. 3, who beat the Swiss player at the Australian and French Opens.
"It's one of the matches of my career," Warinka said. "I served really well -- I think that was the key."
Warinka will meet defending champion Fernando Gonzalez, who beat 18-year-old Juan Martin Del Potro of Argentina 5-7, 6-4, 6-4.
Chile's Gonzalez is ninth in the ATP race and vying for another Masters Cup berth.
He's reached the final of his last two events, in Vienna and last week in Madrid.