Serena beats Venus in WTA championships final

Serena broke twice in the first set and lost just seven points on serve in her last match of the year. She looked sharper than Venus in every facet of a match that featured few long rallies and little of the spectacular tennis the two have provided in some of their previous meetings.

"It feels great," said Serena, who also won the WTA Tour's season-ending event in 2001. "I totally didn't expect to come here and win."

It was Serena's fourth straight win over her sister. She also beat Venus in the round-robin stage of the Doha tournament, the Wimbledon final and the semifinals in Miami this year.

"Playing a final against Venus is really tough," Serena said. "Even though she wasn't really feeling great, she kept hitting every ball back."

Serena pockets $1.55 million for the win after finishing the event undefeated.

Venus, who lost two of her three round-robin matches but still advanced to the semifinals, looked tired after rallying for a three-set win over Jelena Jankovic on Saturday. Venus played with her left knee strapped, while Serena had strapping on her left thigh.

Serena, who advanced after U.S. Open finalist Caroline Wozniacki retired injured in the semifinals, held five of her last seven service games at love and lost just one point in each of the other two.

It was her third tournament win of the season after taking the Wimbledon and Australian Open titles.

"I haven't won a tournament that wasn't a Grand Slam in a while, so that was even more exciting," she said. "My losing streak in (other) tournaments in over."