Serena Williams will miss Madrid next week.
The 23-time Grand Slam champion has withdrawn from next week's Mutua Madrid Open as she needs more training time to prepare for her return to the pro circuit.
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"We regret the absence of Serena and we wish her a speedy recovery," said tournament director Manolo Santana. "She is one of the great champions of our sport, she has always offered a show to the tournament and we hope to see her again at the Caja Mágica in the future."
Williams defeated Victoria Azarenka to win the 2012 Madrid title and topped Maria Sharapova to successfully defend her title in 2013.
The 36-year-old Williams has not played a match since her straight-sets loss to Indian Wells champion Naomi Osaka in her Miami opener in March.
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