"I regret to announce I am withdrawing from the 2012 Australian Open. After several months of training and treatment, I am making steady progress to top competitive form. My diet and fitness regimen have allowed me to make great strides in terms of my health and I am very close to being ready to return to WTA competition. I have every intention to return to the circuit in February."
Williams, a former World No.1, was ranked as high as No.2 in the summer of 2010 before a difficult last year and a half, a period in which she has struggled with injury and illness and competed in only five tournaments (US Open in 2010 and Australian Open, Eastbourne, Wimbledon and US Open in 2011).
With seven Grand Slam titles to her name, Williams' withdrawal means a major contender is sidelined, regardless of her No.100 ranking. Her two best Slams are Wimbledon (five titles, three more finals) and the US Open (two titles, two more finals). She has been to only one final at the Australian Open (2003) and one at the French Open (2002), losing to Serena Williams both times.