Key Biscayne, March 27:

Previous two champions Kim Clijsters and Svetlana Kuznetsova in the fourth round of the Sony Ericsson Open on Monday. Clijsters was caught from behind by Li Na of China 4-6, 6-4, 6-2 and defending champ Kuznetsova lost to Shahar Peer of Israel 6-4, 4-6, 6-3.

Former three-time champion Serena Williams set up a showdown with top-seeded Maria Sharapova and second-seeded Justine Henin strolled into the quarter-finals by beating Vera Zvonareva of Russia 6-3, 6-2.

In men’s play, top-ranked Roger Federer beat Nicolas Almagro of Spain 7-5, 6-3 to reach the fourth round.