Williams sisters in final

Defending champion Venus rallies past Jankovic

Serena, who will end the year as world number one for the first time since 2002, moved past Caroline Wozniacki after the Dane pulled out with a stomach injury when trailing 6-4, 0-1.

"I wasn't playing great. I think it's hard to play well against a player who's injured and is so nice," Serena told reporters. "I'm going to have to really improve my game against Venus if I want to win."

The Williams sisters have already met in the Qatari capital this week, Serena winning a three-set classic in their Maroon Group clash which was their 22nd career duel.
As if they have not already played big enough roles in the WTA year-end showpiece they will also be in the doubles final if they beat Spain's Nuria Llagostera Vives and Maria Jose Martinez Sanchez later on Saturday. Venus seemed down and out after defeat by her younger sister followed an opening group loss against Elena Dementieva. After beating Svetlana Kuznetsova though, some complicated maths edged her through to the last four by virtue of sets won.

It was all a bit unconvincing again on Saturday as the seven-times grand slam champion sprayed errors around the court and also needed treatment on her knee several times.
Gradually she turned things in her favour after Jankovic committed the cardinal sin of failing to finish off a Williams sister when the chance presented itself.
Venus, 29, is the first player to reach the final after losing two matches in the round robin stage since Amelie Mauresmo in 2003. "In the first set I couldn't feel the ball and couldn't seem to get a ball in," said Venus.

"But this is my last tournament of the year so I wss giving 1,000 percent," added the American who has played four three-set matches at the Khalifa Tennis Centre totalling nearly eight hours. "It's wonderful to be playing Serena in the final. I'm so excited. It's the way I wanted to end the year."

Jankovic, who also enjoyed good fortune to qualify for the last four when Dinara Safina retired after two games of their White Group clash on Wednesday, broke serve at 5-5 in the first set and then held her own to go ahead.
Venus appeared to be struggling more in the stifling humidity and served two double faults at 2-2 in the second to trail 0-40 only for Jankovic to let her opponent off the hook with some wasteful errors.

The Serb then saved two break points in the next game but Venus seized her chance when a third opportunity arose.

Jankovic broke serve early in the deciding set but surrendered her own delivery three times in a row and although she did hang on at 3-5, Venus clinched victory in the next game with a forehand that dropped off the net tape.

"It's disappointing. I had so many chances. I had a lot of break points in the second set but then I let everything slip away," said Jankovic who has slipped to number eight in the rankings after being number one in January. "That was my last match of the season."
Wozniacki, too, looks in need of a rest. The world number four, who suffered agonising cramps during her group match win against Vera Zvonareva on Thursday, led 2-0 against Serena but then fell away. "I had a great year. I did all I could. I used all my strength but today I just didn't have any more left," said the 19-year-old U.S. Open runner-up. "What I've learned is I'm a huge fighter."