2013 US OPEN Day 5: Sloane, Serena, Li, Aggie Win; Hewitt Ousts Delpo

Sloane Stephens and Serena Williams both won their third round matches on Friday, setting up their second high-profile meeting in a grand slam this year. Surprisingly, the 20-year-old won the earlier match in the quarterfinals of the Australian Open and I'm sure the 16-time major champion will take this meeting between the two top-ranked Americans very seriously. It will probably be the featured match on Sunday, when yours truly will be attending the tournament. However, since it will almost certainly be on Arthur Ashe stadium, I will not be seeing it live.

Most of the other top seeds in the women's draw advanced: Li Na, Agnieska Radwanska, Victoria Azarenka and Angelique Kerber but #4 seed Sara Errani and  #7 seed Petra Kvitova were both upset.

The big result of the day was 2001 US Open champion Lleyton Hewitt beating 2009 US Open champion Juan Martin del Potro 6-4, 5-7, 3-6, 7-6(2), 6-1 in a rough 5-set match that lasted well over four hours.