NEW YORK: Kim Clijsters of Belgium won the US Open for the second time on Sunday, defeating Caroline Wozniacki of Denmark 7-5, 6-3 to complete one of the most stunning comebacks in modern sports history.

In so doing, she became the first mother to win a Grand Slam title since Australian Evonne Goolagong in 1980 and the first wildcard, man or woman, to win a US Open title in the history of the tournament. The win came just five weeks after she returned from a 27-month retirement.

The 26-year-old Clijsters won her only Grand Slam title here in 2005 after losing four finals, three to compatriot Justine Henin and one to Jennifer Capriati of the United States. She was unable to defend the title the following year as she was injured and then in May, 2007, she rocked the tennis world by retiring, saying that she had had enough of injuries and the tennis lifestyle.

In her time away from the sport, she married and had a daughter and it was only at the start of the year that she started to consider a comeback. That came in Cincinnati in early August, and Flushing Meadows was just her third tournament since she returned.

True to form, Clijsters defeated sisters Serena and Venus Williams on her way to the final. Clijsters is only the third mother to a Grand Slam title after Australians Goolagong and Margaret Court. Goolagong won the 1980 Wimbledon while Court claimed the Australian, French and US Open, all three in 1973.

On the men's draw, Swiss Roger Federer set up a champiomship date with Argentine Juan Martin del Potro. Federer punctuated his latest victory with a shot he described, quite simply, the greatest of his life: a between-the-legs, back-to-the-net, crosscourt winner from the baseline. A point later, with the crowd in hysterics and opponent Novak Djokovic still in shock, the world's top-ranked player closed out the victory, 7-6 (3), 7-5, 7-5, to move one win from his sixth straight US Open title.

Juan Martin del Potro of Argentina earlier handed Rafael Nadal his worst loss in a major tournament, beating the Spaniard 6-2, 6-2, 6-2 to reach his first Grand Slam final and a meeting with Federer, who made his 17th in the last 18.

Serbia's Djokovic fought for more than two and a half hours, hanging with Federer and even grabbing two break points late in the third set to briefly see a glimmer of hope. Some things, though, you simply can't defend, and the winner Federer hit to set up match point was the perfect example. It's the kind of shot every tennis player has tried, and one the world No 1 actually practices.

Serena fined

NEW YORK: Serena Williams was fined $10,500 on Sunday for her angry outburst at a line judge that ended a US Open semi-final and the incident is being investigated by the Grand Slam Committee.

US Open tournament referee Brian Earley said in a statement that Williams has been levied the maximum possible fine for unsportsmanlike conduct, $10,000, plus a $500 fine for racquet abuse. The fine is a mere pittance, even at maximum strength, since Williams received $375,000 for her semi-final run. But the probe underway could bring more penalties. US Open officials were reviewing videotapes of the confrontation and the bizarre ending to her loss to Belgium's Kim Clijsters. — AFP