Serena Williams reached the Miami Open fourth round with a 6-1 , 6-1 victory over 15-year-old CiCi Bellis . The American teenager will play in Saturday's third round, where she faces another American, Madison Keys, who beat her 6-4, 6-2 on Thursday. Andy Murray cruised to a 6-3 6-4 victory over Santiago Giraldo .
Serena Williams reached the Miami Open fourth round with a 6-1 , 6-1 victory over 15-year-old CiCi Bellis . World No 1 will play Svetlana Kuznetsova in the next round . Andy Murray cruised to a 6-3 6-4 victory over Santiago Giraldo .