Williams said Saturday that her knee “just isn’t ready to compete” and a doubles reunion with Venus will have to wait.

Serena Williams, 44, did not ask for medical treatment during a 6-3 6-7 (6) 6-3 loss to 20-year-old Maya Joint of Australia in the first round on Tuesday. | Tennis News

Serena Williams suffered a right knee injury during her Wimbledon comeback, putting her long-awaited doubles reunion with sister Venus in doubt.