World number one Serena Williams defeated Li Na of China to win her second successive WTA Championship, 2-6, 6-3, 6-0 on Sunday and capped off the best season of her legendary career.

Yahoo! Sports reports that in beating Li Na, Williams became just the eighth woman in history to win 11 or more titles in a year and the first to do so since Martina Hingis recorded 12 titles in 1997.

Williams also earned the distinction of winning her fourth WTA Championship which she also won in 2001, 2009 and 2012. She also successfully defended the WTA title, the first to do so since Justine Henin in 2007.

The American tennis player has looked unstoppable this year, winning 78 out of 82 matches. She will once again be on top of the women's rankings for the third time after doing so in 2002 and 2009.

The WTA final was played by two players who are over 30 years old, the first time in the 43-year history of the championship. Williams is 32 while Li is a year younger but both players have been playing superb tennis for the entire year. Li will end up number three in the world rankings at the end of the year.

The match began with Li dominating Williams early on, as the American looked lost following a close win over Jelena Jankovic. But Williams came back strong in the second set and dominated the third set to close out the Chinese and cap off a strong year.