Serena Williams retired from her first-round match at Wimbledon on Tuesday against Aliaksandra Sasnovich due to a right leg injury. Holding a 3-1 lead in the first set, Williams slipped and needed to take an injury timeout at the game's conclusion to receive treatment. She returned to the court, but her movement was visibly limited. Williams was serving in the fifth game at Centre Court when she lost her footing near the baseline while hitting a forehand. She winced and stepped gingerly between points, clearly troubled. After dropping that game, she took a medical timeout and tried to continue playing. A crying Williams bit her upper lip and covered her face between points as the crowd tried to offer support and encouragement. But eventually, the 39-year-old American dropped to her knees, and the chair umpire came over to check on her. The match ended at 3-all in the first set. Williams, a seven-time Wimbledon singles champion, gave an emotional wave to the crowd and...