Third seed Andy Roddick took revenge on Marat Safin for his Australian Open defeat on Monday with a 7-6, 6-2 victory in the third round of the Pacific Life Open.
Twice defending champion Lleyton Hewitt of Australia failed to find his form in the sweltering heat, however, and fell to Argentine Juan Ignacio Chela 6-3, 4-6, 6-1.
Top seed and Australian Open champion Roger Federer continued his determined march through the draw downing Chile's Fernando Gonzalez 6-3, 6-2
U.S. Open champion Roddick, serving with authority and charging the net at every opportunity, beat the 21-year-old Russian for the first time in three meetings.
Roddick, who lost a five setter to Safin at the Australian Open quarter-finals, played a more aggressive and ambitious match than he did in Melbourne, using the net rather than his normal style of booming shots from the baseline.
"He definitely didn't play as well as he did in Australia, but I did a couple of different things that had an effect on that, like coming in a little more, not being as predictable," Roddick said.
Hewitt, who had dominated the field here the last two years, failed to establish his ground attack against Chela.
The Australian partly blamed heavier tennis balls for the defeat. "I didn't feel like I played too badly but he didn't miss a lot of balls out there," Hewitt said.
"(The balls) are heavy and it's hard to hit winners, especially when he's standing a couple of metres behind the baseline running everything down."
Fourth seed Guillermo Coria of Argentina also moved ahead beating Max Mirnyi of Belarus 6-4, 7-5.
Fifth seed Andre Agassi overwhelmed Slovakia's Dominik Hrbaty 6-2, 6-4, while Britain's ninth seed Tim Henman beat Alex Corretja of Spain 6-4, 6-4.
In the women's competition, top seed Justine Henin-Hardenne crushed Marta Marrero 6-1, 6-2 and was joined in the fourth round by fourth seed Anastasia Myskina of Russia, a 2-6, 6-4, 6-3 winner over Venezuelan Maria Vento-Kabchi.
Former Wimbledon champion Conchita Martinez, seeded 11th beat Lisa Raymond, while and 12th seed Svetlana Kuznetsova beat Australian Alicia Molik 3-6, 7-6, 6-2.
Paola Suarez, seeded 18th fell 6-3, 6-4 to Austria's Barbara Schett.
Sixteenth seed Maria Sharapova of Russia won her third round match against the youngest player in the draw, 14-year-old wildcard Sesil Karatancheva of Bulgaria, 3-6, 6-3, 6-2.