As expected, Serena Williams announced that she will not play at Wimbledon 2006, citing a nagging knee injury. Williams had previously announced that she would not return to action until late this summer, which meant she would miss both the French Open and Wimbledon. The French Open commences Sunday in Paris, while Wimbledon will get underway June 26. The 24-year-old Williams is a seven-time Grand Slam champion, including back- to-back Wimbledon titles in 2002 and 2003 when she topped her older sister Venus in both finals. The three-time Wimbledon titlist Venus was last year`s winner at the All England Club. The former world No. 1 Serena was a third-round loser at the Australian Open back in January, marking her only tour action of the year.