Both Serena and Venus Williams have announced their withdrawal from the 2012 China Open, set to begin this weekend in Beijing. Serena is battling lingering effects of the flu, while Venus is suffering from a back injury. Serena won the China Open title in 2004.
Serena's own Twitter account carried a short message saying: ''Flu no fun,'' but made no mention of the China Open. Williams also missed last year's tournament with an injury. Serena is enjoying a very successful 2012 to date, having captured the Wimbledon title, the U.S. Open title and Olympic Gold at the 2012 London Games.
Venus, currently ranked 41st in the world, was diagnosed last year with Sjogren's Syndrome, an autoimmune disease that causes fatigue and joint pain, and has played a light schedule ever since.