Clijsters sinks Serena and makes US Open final

Kim Clijsters of Belgium reacts during her semi-final match against Serena Williams at the U.S. Open tennis tournament in New York September 12, 2009. Clijsters won the match 6-4 7-5, which ended in controversy when the American was called for a foot-fault on a second serve to go match point down. The Belgian, playing in only her third tournament after taking a two-year break to start a family, became the first mother to reach a grand slam final since Evonne Goolagong achieved the feat at Wimble

Serena Williams (L) of the U.S. talks with tournament referee Brian Earley (C) and an official during her semi-final match against Kim Clijsters of Belgium at the U.S. Open tennis tournament in New York, September 12, 2009. Clijsters won the match 6-4 7-5, which ended in controversy when Williams was called for a foot-fault on a second serve to go match point down. (Xinhua/Shen Hong)

Serena Williams of the U.S. hits a return to Kim Clijsters of Belgium during their semi-final match at the U.S. Open tennis tournament in New York, September 12, 2009. Clijsters won the match 6-4 7-5, which ended in controversy when Williams was called for a foot-fault on a second serve to go match point down. (Xinhua/Shen Hong)

Kim Clijsters of Belgium hits a return to Serena Williams of the U.S. during their match at the U.S. Open tennis tournament in New York, September 12, 2009.(Xinhua/Shen Hong)

Serena Williams reacts during her semi-final match against Kim Clijsters of Belgium at the U.S. Open tennis tournament in New York, September 12, 2009. Clijsters won the match 6-4 7-5, which ended in controversy when Williams was called for a foot-fault on a second serve to go match point down. (Xinhua/Shen Hong)

NEW YORK, Sept. 13 (Xinhua) -- Former World No. 1 Kim Clijsters reached the U.S. Open women's singles final at her first comeback grand slam on Saturday with a controversial straight sets win over Serena Williams.

The Belgian beat the defending champion 6-4, 7-5 after a day-long rain delay to advance to the final just weeks after returning to the tour from a two-year break to start a family.

Trailing 5-6, 15-30 in the second set, Williams whacked her second serve but was called a foot-fault by the lineswoman and put at match point down.

The fierced Williams was then seen roar at the lineswoman and given a point penalty to lose the match.

The other semifinal of the women's singles sent in teenage Dane Caroline Wozniacki, who defeated unseeded and error-prone Belgian Yanina Wickmayer 6-3, 6-3.

Later on Saturday, the women's doubles semifinal between third seeds Samantha Stosur/Rennae Stubbs of Austria and top seeded Cara Black of Zimbabwe and Liezel Huber of the United States was suspended while the former duo led 7-5.

On the men's part, third seed Rafael Nadal needed just 34 minutes to complete a postponed 7-6, 7-6, 6-0 victory over Chile's Fernando Gonzalez.

Nadal will face sixth seed Argentine Juan Martin del Potro in Sunday's men's semifinals, while five times champion Roger Federer faces fourth-seeded Serb Novak Djokovic on the same day.