Olympics: Quarterfinals

The quarterfinals are set in tennis at the Olympic Games in London, and three of the eight remaining players will receive medals in a few days time.  Somewhat surprisingly, each draw has held close to form with 5 of the top 8 men's seeds still alive and 6 of the top women's seeds.  The only unseeded player is Clijsters, who has played little in the past year.  There have been really no major underdogs moving far in the draw, though players such as Hewitt, Baghdatis, and Venus reached the round of 16. Here are the remaining players:

Men
1) Roger Federer (SUI)
2) Novak Djokovic (SRB)
3) Andy Murray (GBR)
5) Jo-Wilfried Tsonga (FRA)
8) Juan Martin Del Potro (ARG)
10) John Isner (USA)
11) Nicolas Almagro (ESP)
15) Kei Nishikori (JPN)

-Eight different nations are represented, but who would have thought Almagro would be the last remaining Spaniard?
-Tomorrow's quarters matchups are Federer/Isner, Del Potro/Nishikori, Murray/Almgaro, and Djokovic/Tsonga
-Djokovic and Federer are the only returning quarterfinalists from the Beijing Olympics in '08.  Djokovic would go on to win the bronze but Federer lost in the QF to Blake.

Women
1) Victoria Azarenka (BLR)
3) Maria Sharapova (RUS)
4) Serena Williams (USA)
6) Petra Kvitova (CZE)
7) Angelique Kerber (GER)
8) Caroline Wozniacki (DEN)
14) Maria Kirilenko (RUS)
Kim Clijsters (BEL)

-Seven different nations are represented, only Russia has two.  They swept the medals in '08.  The US is the only nation with players remaining in both draws.
-Tomorrow's quarters matchups are Azarenka/Kerber, Williams/Wozniacki, Sharapova/Clijsters, and Kvitova/Kirilenko
-Serena is only returning quarterfinal from Beijing in '08, but she lost there to gold-medalist Dementieva in the QF.