Serena Williams ruthlessly ended the challenge of 15-year-old wildcard CiCi Bellis to ease into the fourth round of the Miami Open on Sunday . Williams , ranked No 1 in the world , was taking on the game 's junior No 1 in a clash of generations , and unsurprisingly it was the top seed who came through against her fellow American . The 33-year-old triumphed 6-1 6-1 to set up a last-16 clash against former two-time grand slam champion Svetlana Kuznetsova , who ended the challenge of 13th seed Angelique Kerber 6-3 3-6 6-3 . Serena Williams moved into the fourth round at the Miami Open for the loss of only two games . The world No 1 was too powerful for 15-year-old wildcard entry CiCi Bellis . Third seed Simona Halep was a 6-4 7-5 winner over Camila Giorgi , but the 30th seed 's Italian compatriots fared better . Fifteenth seed Flavia Pennetta defeated former world No 1 Victoria Azarenka 7-5 7-6 ( 8/6 ) and Sara Errani , seeded 11th , booked her spot in the last 16 after hitting back to oust Garbine Muguruza 4-6 6-4 6-1 . Elsewhere , Switzerand 's Belinda Bencic knocked out German qualifier Tatjana Maria 6-4 7-5 . Former world No 1 Victoria Azarenka crashed out after losing two close sets to Flavia Pennetta . In the men 's draw , British third seed Andy Murray cruised to a 6-3 6-4 victory over Santiago Giraldo with the minimum of fuss . Murray continued the commanding form he displayed in seeing off Donald Young on Friday and his Colombian opponent , seeded 27th , had no answer . British No 1 Andy Murray made light work of his match against Santiago Giraldo . Murray 's fiancee Kim Sears shields herself from the Florida sunshine while watching her man . There were , however , shock defeats for seventh seed Stan Wawrinka and Jo-Wilfried Tsonga , seeded 11th and playing in his first competition this year . Wawrinka was edged out by Adrian Mannarino 7-6 ( 7/4 ) 7-6 ( 7/5 ) , while Tsonga was sent packing after a 6-4 7-6 ( 7/4 ) defeat to French compatriot Gael Monfils . Fifteenth seed Kevin Anderson beat Leonardo Mayer 6-4 6-4 while Austria 's Dominic Thiem came through 6-4 6-3 against Jack Sock of the United States .
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 6-4 6-3 6-4 victory over Santiago Giraldo .