- World number one Serena Williams has pulled out of upcoming WTA tournaments at Indian Wells and Miami because of a knee injury, organisers said. A statement issued by BNP Paribas Open organisers in California quoted Williams as saying she was withdrawing because of a problem with her left knee. "Sadly, I have to withdraw from the BNP Paribas Open in Indian Wells and the Miami Open," Williams said. "I have not been able to train due to my knees and am disappointed I cannot be there." Williams, 35, has not played since defeating sister Venus in the final of the Australian Open in January to clinch a record 23rd Grand Slam singles title. The American star finished runner-up in the Indian Wells final last year, a tournament she only started playing again in 2015 after a 13-year boycott.