Sony Ericsson Championships Doha 2009

DOHA, Qatar - When Serena won the Tour Championships in 2001 she was denied a joyful match point moment because Lindsay Davenport was injured and unable to contest the final. Today may well bring more mixed emotions for the 28-year-old, for victory can only come at the expense of her sister, Venus.

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[7] Venus Williams (USA) vs. [2] Serena Williams (USA)
S.Williams leads 12-10
There's not much new to be said about these amazing athletes, but the fact they are meeting in the final of the Tour Championships for the first time speaks volumes of their enduring capacity to push themselves. Serena has certainly had the better week, arriving in the final undefeated, but Venus - only the second player to reach the final after winning just one round robin match since Amélie Mauresmo in 2003 - was surely boosted by her semifinal defeat of Jelena Jankovic, against whom she was 4-5 going in. Serena holds a 7-3 edge over her sister in finals, and if she wins today she'll emulate the likes of Justine Henin, the most recent player to win two Slams and the Tour Championships in the same year. If Venus prevails, she'll join a select group that has won back-to-back SEC titles - a club that includes Henin, Kim Clijsters, Steffi Graf, Monica Seles, Martina Navratilova and Chris Evert. In fact, those players, plus Evonne Goolagong Cawley, Gabriela Sabatini and Martina Hingis are the only women who have ever won this title more than once twice. Whoever triumphs today will be a very worthy addition to that illustrious list.