Coming up Thursday, there is really only one marquee match of note. This will be a rematch of the 2005 semifinal between former world No. 1 and Australian Open Champion "Rusty" Lleyton Hewitt and former world No. 1 and United States Open champion "A-Rod" Andy Roddick.
But as we saw Tuesday with Mardy Fish, any seeded player can have an off day, and interesting things can happen. In the next few pages we'll take a look at a few matchups of Day 4 for their upset potential.