from www.tennisone.com... here are the facts, no guesses...
San Diego - No Round In Particular
Serena Williams -- WITHDRAWN
This is it. The #1 ranking is on Kim Clijsters' racquet.
Well, just barely. It's going to be a very, very, very close thing.
First, the story of what happened. Serena, who last week withdrew from Stanford with a knee problem (believed to be tendonitis), has now withdrawn from San Diego as well. Since she didn't withdraw until after play began, seeds will not be promoted; Meilen Tu will take her place as a Lucky Loser. It has not been announced, but it appears that Serena will be fined for two consecutive late withdrawals.
But the real penalty is bigger: She might lose the top spot, at least for a week. Here is the situation: Serena leads Kim Clijsters by 264 points. However, Clijsters has 122 points in her seventeenth tournament, meaning that she has to earn 386 points to pass Serena.
Can she do it? Yes, barely -- if the seeds hold. This is a bonus Tier II, so it's worth 220 points. And, as the draw stands, Clijsters's path to the title is:
Second round: Virginia Ruano Pascual (8 quality points)
Third round: Meghann Shaughnessy (23 quality points)
Quarterfinal: Ai Sugiyama or Conchita Martinez (35 quality points)
Semifinal: Lindsay Davenport (50 quality points)
Final: Justine Henin-Hardenne (66 quality points)
Grand total: 402 points. That means Clijsters has a margin of error of 16 points. That means she can accept only one substitution: If she faces Chanda Rubin rather than Lindsay Davenport in the semifinal, she's still all right. (The withdrawal of Nathalie Dechy genuinely hurt her: Had Dechy been in the draw, she would have had a 31 point margin, and would not have needed to face Henin-Hardenne in the final.)
Even if Clijsters doesn't make it this week, she can all but guarantee herself the top spot at some future time by doing well here. It's going to be a very interesting week.