RIO DE JANEIRO, Brazil - How many minutes has Madison Keys spent on court? Who has hit the most aces? And in whose famous footsteps is Johanna Konta looking to follow? These are just a few of the questions answered in an Olympic quarterfinal edition of wtatennis.com's By The Numbers.
92 - In the 1924 Paris Games, Kathleen McKane won doubles silver and singles bronze to increase her career medal tally to five, a total that is yet to be matched by any player, male or female. Johanna Konta is attempting to become the first Briton since then to collect a medal at the Games. Puig and Elina Svitolina are bidding to become the first medalists from Puerto Rico and Ukraine, respectively.
44 - Her upset of Garbiñe Muguruza took Puig's match win for the season to 44. By contrast, the Puerto Rican registered just 20 in the whole of 2015.
19 - At 19 years old Daria Kasatkina is the youngest player left in the singles draw. Only four teenagers have won an Olympic singles medal: Steffi Graf (1988 - gold), Gabriela Sabatini (1988 - silver), Jennifer Capriati (1992 - gold) and Elena Dementieva (2000 - silver).
13 - Keys, Konta and Petra Kvitova have all struck 13 aces across their first three matches. Siegemund, meanwhile, has hit just one.
9 - Before Rio, Kvitova had not reached a quarterfinal since Stuttgart in mid-April. Svitolina's wait was even longer, not reaching this juncture since lifting the title in Kuala Lumpur in early March - a run stretching nine tournaments.
7 - Germany is one of seven different nationalities represented in the semifinals.
6 - Six of the eight quarterfinals are Olympic debutantes.
2 - The only two with previous Olympic experience, Kerber and Kvitova, exited at the quarterfinal stage four years ago in London.
0 - The number of sets Kerber and Puig have lost en route to the quarterfinals. London 2012 gold medalist Serena Williams is the only player to win the competition since without dropping a set since the sport's reintroduction to the Olympics.