The highest-profile match today occurs at night, after 7 p.m. ET, when No. 2 seed Roger Federer plays in prime time. Watch to see if Federer unleashes his newly developed weapon, which he calls SABR. It stands for Sneak Attack By Roger, and it has him, rarely and very unexpectedly, rushing forward as his opponent serves, to meet the incoming serve about midcourt. Otherwise, it’s one day and counting before Serena and Venus Williams play in the next round – on opposite sides of the net.