Three-time champion Roger Federer moved through to the semifinals at the Pacific Life Open when Tommy Haas withdrew prior to their quarterfinal match with a sinus infection, Friday afternoon in Indian Wells.

"I deeply regret that I have to withdraw from the Pacific Life Open," said Haas. "I was playing my best tennis of the season, and was looking forward to playing Roger Federer this afternoon. I am sure the tennis will be incredible this weekend, and look forward to returning next year."

Federer, who will next play American Mardy Fish as he attempts to reach his first final of 2008, said: "I am very sorry for Tommy as I was looking forward to another great match with him. We have played quite a few times, and I know and respect Tommy a lot. I hope he gets better quickly."

The 29-year-old Haas was looking to snap a seven match skid against Federer, who leads their career series 8-2. Haas’ only wins over the Swiss came in two of their first three meetings, at the 2000 Sydney Olympics and at the 2002 Australian Open.

Haas had reached the Indian Wells quarterfinals for the second straight year, compiling an impressive run with wins over Julien Benneteau, No. 6 Andy Roddick, No. 30 Fernando Verdasco and No. 11 Andy Murray.

Coming into Indian Wells, the former World No. 2 had won just two ATP matches through four tournament appearances this year. He underwent shoulder surgery last November and missed the first few weeks of the season.

The 26-year-old Federer has enjoyed a flawless tournament, confidently making his way past Guillermo Garcia-Lopez, Nicolas Mahut and Ivan Ljubicic without breaking a sweat. He has a sparkling 21-1 record at this event since 2004, with his only loss coming against Guillermo Canas last year in the second round.

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