Doha, Qatar - Serena Williams has the chance to consolidate her year-end number one ranking Sunday in a family fight with her sister Venus in the final of the Sony Ericsson Championships. Serena, who was assured of the 2009 top spot at mid-week when rival Dinara Safina withdrew with back pain, got a free ride into the title match as teenaged US Open finalist Caroline Wozniacki was unable to go on in a 6-4, 0-1 semi-final loss on Saturday.
The Dane has been plagued this week in the desert by cramps after winning marathons and struggling at times to stay on her feet due to her fitness issues.
Saturday's final was a match too far for the world number four youngster as she fell to Williams while able to play for just three-quarters of an hour.
The problem Saturday was a stomach muscle after the teenager lost four service games in the opening set.
"She's been struggling throughout the entire tournament," said Serena Williams, the only woman in the eight-strong field to win all three of her group matches.
"She's an incredible fighter coming out here and here putting out the effort."
Serena Williams and her sister have met in the last two Wimbledon finals, splitting those, with Serena standing 12-10 in the series dating back to 1998.
Holder Venus Williams came from a break down in the final set as a catch-up battle resulted in a second straight trip to the final 5-7, 6-3, 6-4 over Jelena Jankovic.
She was treated for a knee problem but shrugged off the complaint ahead of the decider.
"I couldn't really feel the ball well in the first set. I couldn't seem to get a ball in the court. But as this is my my last tournament of the year, I'm giving 1,000 percent," she said.
Venus Williams had to strive in the comeback which took more than two and a half hours against Jankovic, who finished 2008 on the top position.
William lost the first set but managed to claw back over the course of the struggle, immediately breaking back in the final set after going down.
The 28-year-old American, ranked seventh, stood 4-5 against Jankovic going into the match, but had won their last meeting at the season wrap-up event a year ago at the same semi-final stage.
Jankovic earned a break point in the final game, which Williams saved. The American then secured a match point, which she converted to end the battle in which she double-faulted ten times.
That worry statistic was eased somewhat by her 10 aces and five breaks of the Jankovic serve. Williams saved nine of the 13 break points she faced.
"I had to come back against a consistent player like Jelena," said Williams.
