Serena withdraws from Italian Open with knee problem

Serena Williams withdrew from the Italian Open on Tuesday with a recurring left knee injury. Serena Williams has withdrawn with a new knee pain, organisers said. The 23-time Grand Slam champion's withdrawal comes a day after she beat Sweden's Rebecca Peterson in straight sets to set up a second round meeting with her older sister Venus. She had been returning after more than two months out with a knee problem, in the final warm-up clay-court tournament before the French Open. Four-time Rome winner Serena, 37, had eased through 6-4, 6-2 her first round match against Swedish qualifier Petersen. Serena had also played Petersen in the second round at the Miami Open in March before withdrawing with a knee injury. Her withdrawal sends Venus Williams, the 1999 winner, through to a third round meeting with either Johanna Konta of Britain or American seventh seed Sloane Stephens.