Question: Who has the best head to head record against serena williams?
Disambiguated questions and answers: question: Whoo has the best head to head record against serena williams of number 1 ranked players?
Who has the best head to head record against serena williams of number 2 ranked players?
Who has the best head to head record against serena williams of number 3 ranked players?
answer: Arantxa Sánchez Vicario
Petra Kvitová
Elena Dementieva
Natural Questions answer: Paola Suárez
Mary Joe Fernández (from the Wikipedia article "Serena Williams career statistics")