DOHA, Qatar - With Serena Williams the only player who has guaranteed her place in the semifinals, there's still plenty at stake as the final day of round robin action is played out at the Sony Ericsson Championships.

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WHITE GROUP

[4] Caroline Wozniacki (DEN) vs. [8] Jelena Jankovic (SRB)
Jankovic leads 2-0

Wozniacki has risen to new heights since she lost to Jankovic at Wimbledon and the US Open last year, and she has certainly been the player with more mojo of late. But after her dramatic win over Vera Zvonareva yesterday it will take a monumental effort just to be competitive again today. On the other side of the net, Jankovic can still book a place in the semis with a win, and the former world No.1 certainly has the grit and determination to do the job. These two play a similar game, based around resolute counterpunching, so neither will blow the other off the court; the victor will be the one who can keep it up longer - which common sense suggests should be the Serb. But as Wozniacki showed yesterday - quite literally, as she writhed in pain on the court - she is never down for the count. If the 19-year-old prevails, she'll carry Azarenka into the semis with her.

[10] Agnieszka Radwanska (POL) vs. [6] Victoria Azarenka (BLR)
Azarenka leads 2-1

For the second year in a row, Radwanska came to Doha this week as one of two alternates, and once again she has received the call to arms on the last day of the round robin. Twelve months ago she handled the situation well, beating Kuznetsova in straight sets, and the fact that she has nothing to lose today may well help her cause. By contrast, Azarenka, also 20, will be playing for both pride and a spot in the semis. Before it all went wrong after the first set of her match against Wozniacki on Wednesday, her semifinal berth had seemed assured, but once again her mental game has been called into question. She can't afford to let things get to her today, for her Polish rival is a cool customer - and although she doesn't strike the ball with the same ferocity as the Belarusian, she makes up for it with all-court craft and smarts.

MAROON GROUP

[3] Svetlana Kuznetsova (RUS) vs. [5] Elena Dementieva (RUS)
Kuznetsova leads 6-4

Following her defeats at the hands of Serena and Venus, Kuznetsova can't qualify for the semifinals, but after eight straight losses at the Sony Ericsson Championships over the last three years a morale-boosting win might help future campaigns. At the same time, she holds considerable power over Dementieva's destiny in the competition, because defeating her compatriot would give Venus the second semifinal berth in the Maroon Group. Coming after her superb victory over Venus on day one, Dementieva must have been disappointed with her showing yesterday against Serena, a player against whom she has had considerable success over the years. To be fair, though, Serena played extremely well. On balance, Dementieva should be more fired up today, and that could make the critical difference.

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