Nadal pasted Mikhail Ledovskikh, 6-4, 6-0, and Roddick stopped Paul-Henri Mathieu, 6-3, 6-4, to set up Thursday's marquee quarterfinal match. Nadal owns a 2-1 career edge over Roddick but they've played only once since 2004. Last year, Nadal was a straight-set winner over Roddick in a Master Series tournament in California.
No. 3-seeded Novak Djokovic was a straight-set winner over Fabrice Santoro, 6-3, 7-6 (7-3), while fourth-seeded David Ferrer and fifth-seeded Nikolay Davydenko also won Wednesday. Ferrer dropped Olivier Rochus, 3-6, 7-5, 6-1, and Davydenko stopped Jan Hernych, 6-1, 6-4.
In addition to the Nadal-Roddick match, Thursday's card has Djokovic playing Andreev, Ferrer going against Lopez and Davydenko meeting Murray.
The 2008 Dubai champion will take home $300,000.