Tuesday ResultsAt Melbourne ParkMelbourne, AustraliaPurse: $15.44 million (Grand Slam)Surface: Hard-OutdoorSinglesMenQuarterfinalsAndy Roddick (7), United States, def. Novak Djokovic (3), Serbia, 6-7 (3), 6-4, 6-2, 2-1, retired.Roger Federer (2), Switzerland, def. Juan Martin del Potro (8), Argentina, 6-3, 6-0, 6-0.

WomenQuarterfinalsVera Zvonareva (7), Russia, def. Marion Bartoli (16), France, 6-3, 6-0.Dinara Safina (3), Russia, def. Jelena Dokic, Australia, 6-4, 4-6, 6-4.