Article Photos: S. Williams, Federer ease into US Open's 4th round



Serena Williams returns a shot to Russia's Ekaterina Makarova in the third round of play at the 2012 US Open tennis tournament, Saturday, Sept. 1, 2012, in New York. (AP Photo/Mike Groll)

Serena Williams returns a shot to Russia's Ekaterina Makarova in the third round of play at the 2012 US Open tennis tournament, Saturday, Sept. 1, 2012, in New York. (AP Photo/Mike Groll)