World number one Serena Williams has pulled out of next week's Swedish Open after failing to recover from the illness which dramatically ended her Wimbledon campaign.

The 32-year-old American star, who was the defending champion at the Bastad claycourt event, withdrew from the Wimbledon doubles event after suffering from what the WTA described as a “viral illness”.

“I decided not to play in Bastad, because I am still not feeling 100%,” Williams said in a statement released on Thursday.

“I want to be in perfect condition to go back on court, but unfortunately it's not the case. I really hope to be able to get back to training from next week.

“Bastad was my favourite tournament I played in last year, thus I am very disappointed not to come back there. But there is still next year, so I can't wait to go back there.”

Williams was a fourth-round loser in singles at Wimbledon before she retired from her doubles second-round tie with sister Venus after almost fainting and serving up four double faults in a performance which made for uncomfortable viewing. – AFP