Twenty-three time Grand Slam champion Serena Williams has withdrawn from the Italian Open after suffering a knee injury.

 

The American, 37, was set to play sister Venus Williams in the second round but said she would be “concentrating on rehab” instead. “I look forward to seeing you all at the French Open and next year in Rome,” she said.

 

Williams has also struggled with injury pulling out of the Miami Open at the third-round stage in March, after a viral illness prevented her from competing in Indian Wells. The French Open tournament kicks off on 26 May and Williams is chasing her fourth title, while Wozniacki, a former Australian Open champion, has never gone beyond the quarter-final stage.