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



Serena Williams reacts during her match against 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/Kathy Willens)

Serena Williams reacts during her match against 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/Kathy Willens)