Roger Federer just dropped the first set of his Round of 16 match to Mikhail Youzhny in a tiebreaker.
Rafael Nadal just won his first set against Juan Martin del Potro in a tiebreaker, but his left heel is clearly giving him some trouble. He was lucky to win that set.
Serena Williams, Venus Williams and Caroline Wozniacki have all lost already today.
Are we about to lose the two most dominant male players of this generation as well?
Tune into ESPN2 as the network switches between the two matches. For those of you stuck at work, I'll do my best to keep you updated.