Third seed Marat Safin went out of the Nasdaq-100 Open when he was swept aside 7-6, 6-1 by Slovak Dominik Hrbaty in the third round on Sunday.
Safin was followed through the exit door by fifth-seeded Spaniard Carlos Moya, who lost 7-6, 3-6, 6-2 to Swede Thomas Johansson. Number eight David Nalbandian of Argentina also slumped to a 7-6, 6-1 defeat by Spain's David Ferrer.
Amelie Mauresmo, Maria Sharapova and Serena Williams, the top three seeds in the women's draw, made unfussy progress into the last 16.
Mauresmo cruised past Anna Smashnova of Israel 6-2, 6-1, Sharapova routed American Marissa Irvin 6-2, 6-0 and Williams beat Israel's Shahar Peer 6-3, 6-3.
Hrbaty took one hour 16 minutes to overcome Australian Open champion Safin, taking full advantage of his opponent's inability to keep either his temper, or his shots in court.
After losing a first-set tiebreak, the Russian allowed his emotions to get the better of him in the second set, slamming down and kicking his racket and frequently throwing his arms up in exaggerated gestures of despair.
Hrbaty soon went 3-1 up and when Safin's serve again proved to be as fragile as his composure, he broke again and served out for an easy win.
"I really didn't play well. I just couldn't find my game," said Safin, who also lost in the third round of last week's Pacific Life Open in Indian Wells.
"Normally, this month I never play well so for me it's nothing new."
Safin's defeat should ensure that Andy Roddick hangs on to the number three position in the world rankings, despite retiring from his opening match here with a wrist injury.
Unseeded Kim Clijsters extended her streak to 10 wins in a row by defeating 12th seed Nathalie Dechy of France 6-0, 6-2.
The former world number one from Belgium, who won last week's Pacific Life Open title, has lost only one match since returning to the tour last month after being sidelined for most of 2004 with a wrist injury.
Another former world number one from Belgium, 19th seed Justine Henin-Hardenne, continued her successful return to the tour after illness and injury.
Henin-Hardenne, playing her first event since last year's U.S. Open, put out Nuria Llagostera Vives of Spain 6-3, 6-2.
Eighth seed Venus Williams breezed past Colombian Fabiola Zuluaga 6-2, 6-0.
"The scoreline didn't show the intensity with which I had to play to get that scoreline," said Venus. "She's a great player."