Serena Williams will not compete in next week’s Madrid Open, the WTA Tour’s third Premier Mandatory tournament of the season, after coming down with a fever in recent days.

“Unfortunately, I have to withdraw from Madrid because I’ve been battling the flu and I’m not at 100 per cent. I look forward to returning soon,” the American world No.1 said in a statement released by tournament organisers on Friday.

The absence of Williams, a semifinalist last year and champion in 2012 and 2013, makes Poland’s Agnieszka Radwanska the top seed at this elite clay-court event.