The Williams sisters both have fantastically difficult challenges on Ashe today. We’ll preview both matches this morning and find out exactly what their opponents need to do to win.

Meanwhile, Justine Henin gets Dinara Safina in an extremely intriguing night match on Ashe (as we’ve mentioned, playing at night is not Henin’s favorite). Novak Djokovic will follow by playing the young Argentine prospect Juan Martin Del Potro.