I remember watching Serena, Venus with my grandmother: 27-yr-old Sakkari

Talking about 40-year-old Serena Williams and her sister, 42-year-old Venus, world number four Maria Sakkari said she remembers watching both ex-world number one players with her grandmother, adding it's great to still have them on Tour. The 27-year-old further said, "Serena is, in my opinion, the greatest female athlete." Serena and Venus have won 23 and seven Grand Slams respectively.