Serena Williams has withdrawn from Miami due to the knee injury that she sustained or that flared up at the Australian Open.

According to Tennis.com, Caroline Wozniacki will be the # 2 player in the world on Monday and if she has really good results before the French Open, she could overtake Serena as the #1 player in the world.

What a bummer. It must be serious if Serena is withdrawing from Miami, a tournament she has won so many times. I don't even care if she loses the ranking. She needs to take care of that knee. Should be an interesting tournament nonetheless. Perhaps Kim or Justine will come through. Will Azarenka defend her biggest title? Or could there be a surprise champion? We'll see if Jankovic can continue to play well and if Venus can step up in Serena's absence.

Azarenka will probably not defend her title. Most of the top young players are not consistent enough to defend a big title.

Clijsters or Henin might step up and do something at this tournament. But Henin and maybe Clijsters might start to follow Serena's lead by focusing on the majors.

Other than Wimbledon, Venus's chances of winning another major are small. Maybe Venus has adopted the opposite philosophy as Serena by focusing on the smaller events. With Serena out of the way, it would be nice if Venus could win a big tournament that is not a major.