Williams collected her 11th title of the year and became the first player to defend the title since Justine Henin in 2007. The American won her fourth WTA Championship, having captured the elite tournament of the eight top-ranked players also in her debut in 2001 and in 2009 and 2012.
Williams has won 78 of 82 matches this year and will finish the year as the top ranked player for the third time in her career after 2002 and 2009. Li was in her first WTA Championship final and will finish the year at a career-high No 3.
Williams sank to her knees after firing a backhand winner on her second match point. She became the eighth female player to win 11 or more titles in a year and the first since Martina Hingis claimed 12 in 1997.
Li got off to a better start over a sluggish-looking Williams, who struggled a day earlier to beat Jelena Jankovic and complained later of being exhausted after a long season. The Chinese, passing Williams almost at will, was quick to break serve for a 2-1 lead and rolled through the first set, which ended with Williams netting a forehand and hitting a backhand passing shot wide.
Williams won a key game at the start of the second set that went to nine deuces and lasted nearly 12 minutes as the American fended off two break points before finally prevailing with a service winner.
Li blasted an ace, her only one of the match, to level at 3-3. But she produced a double-fault and a forehand error to give Williams a chance to serve out the set. Williams needed three set points to close it out.
It was another double-fault by Li that gave Williams a break of serve at the start of the third and the American never looked back. But she did have to save five break points, the last one with her sixth ace, before wrapping up the title.
In Basel, Juan Martin del Potro denied Roger Federer his hometown Swiss Indoors title for the second straight year, winning the final 7-6 (7-3), 2-6, 6-4.
Federer trailed throughout his first final in more than four months, though showed no sign of the back problems which have hampered him during the most difficult season of his career.
“I am a winner, I don’t take much confidence from losing matches,” Federer said. “I am happy about the level of my play, it’s getting better, but it’s not in losing where I get much confidence.”
Federer had hoped that the raucous crowd support in Basel – where he is a five-time champion – could help revive his form, but he has still won just one title in the past 14 months. Del Potro beat the player he described as “a big inspiration” for the third straight time, including the 2012 Basel final.
“I think Roger is playing well,” the top-seeded Argentine said. “For me, he has the perfect game. He played much better when he has the chance to play the top guys.”
Still, with this loss against fifth-ranked del Potro, Federer has only one victory against a top-ten opponent in 2013. That was back in January, against then No 8 Jo-Wilfried Tsonga in the Australian Open quarter-finals, before a series of shocking defeats by opponents outside the top 50.
Federer’s Swiss Indoors run did all but secure him a place in the eight-man line-up at the ATP World Tour Finals in London starting a week today. The sixth-ranked Swiss would confirm his London place at the Paris Masters in midweek if he wins a second-round match against Kevin Anderson of South Africa or Mikhail Youzhny of Russia. Even with a loss, he can only be kept out by an unlikely sequence of victories for several rivals in the points race.
“Looking forward to Paris and London, he is going to be a really difficult opponent,” Del Potro said. “Then he has the time for recovery to be ready for next season.”
Del Potro earned his 17th career title and fourth this season. He also won at Rotterdam in February, Washington D.C. in August, and Tokyo this month, all on his favoured hard-court surface.
The 32-year-old Federer still holds a 13-5 career record against del Potro, but last beat him in the London Olympics semi-finals at Wimbledon.
Yesterday, Federer lost the first set despite playing some of his best tennis of the week. After del Potro forced a 5-3 lead with the first break, Federer responded with four straight points on his opponent’s serve and shouted in triumph. Facing two set points in the next game, Federer hit an ace and won a long, slugging rally that brought a yell of delight from the sell-out crowd.
Still, del Potro dominated the tiebreaker, helped by two net cords, and clinched the set when Federer sent a forehand wide. Federer levelled the match after breaking to take a 2-0 lead with a forehand crosscourt winner. He broke again to clinch the set, set up by a forehand winner, and got a standing ovation as he headed back to his seat.
But the Swiss quickly wasted the advantage of serving first in the decider. He double-faulted to give del Potro a second break point and then hit a forehand long. “I did hand the break over to him a little bit too easily in the third set but I did well today,” Federer said.
Serving for the match, del Potro hit an ace to set up three match points, and converted the second as Federer failed to deal with his strong ground strokes.