Serena WilliamsTwo-time defending champion, Serena Williams, has withdrawn from the 2011 Australian Open, according to tournament director Craig Tiley.

Williams is blaming her foot injury for the withdrawal. It is the 2nd consecutive Grand Slam tournament that Williams will miss, and the loss of 2000 ranking points will cost her her place in the top 10 rankings.

Williams has played only one exhibition match since winning Wimbledon in July. She had surgery after cutting her foot on broken glass at a restaurant following her win at the All England Club. She returned to practice in September, but twice put off her comeback, missing the U.S. Open, the season-ending WTA tournament, the Fed Cup and a handful of tour events.

She said she had additional surgery last month and couldn’t risk returning before the injury had properly healed.

“As I recently learned, pushing myself back into my intense training too early only caused me further injury and damage,” Williams said. “While I desperately want to be back on the court and competing in the first Grand Slam tournament of the year, it is imperative for my health that I continue to work with my doctors to ensure my foot heals properly.

“This decision, though heavy on my heart, is the right one. I am praying for a healthy recovery and I promise my Aussie fans and my fans around the world that I will be back better than ever as soon as I can be.”

Williams has won the Australian Open five times and is a popular draw in Melbourne.