Sharapova to lose No1 spot

Russian Maria Sharapova will be replaced by Justine Henin as the world's best female tennis player next week, after she lost to Vera Zvonareva in the 4th round of the Pan Pacific tournament in the United States.

Sharapova took the first set 6-4 and was serving for the match at 5-4 in the second. But Zvonareva fought back to break the top seed and held on to win the 7-5.

In a surprisingly one-sided decisive set the 15th seed completely dominated Sharapova to cruise to a 6-1 win.

Zvonareva takes on China's Na Li next.

The No4 seed Nadia Petrova withdrew from her match against Tatiana Golovin and Anna Chakvetadze lost out to Israel's Shahar Peer.

However, Svetlana Kuznetsova will play Nicole Vaidisova in the quarter finals  after beating Ai Sugiyama.

In the men's action Ivan Ljubicic knocked out David Nalbandian. The Big Croatian won in three sets, 2-6, 6-4, 6-2.

Rafael Nadal also went through to the last 8, beating Juan Carlos Ferrero in straight sets. He'll meet Juan Ignacio Chela next.

Home favourite Andy Roddick was a straight sets winner against Frenchman Richard Gasquet.