INDIAN WELLS, Ca. -- Martina Hingis beat second seed Lindsay Davenport 6-3 1-6 6-2 to reach the Pacific Life Open quarterfinals in one of several upsets on Tuesday.

In the afternoon session, Australian Open runner-up Marcos Baghdatis overcame seventh seed Gaston Gaudio 6-7 6-3 6-2 and Czech teenager Tomas Berdych knocked out number nine Lleyton Hewitt 7-5 6-3.

Russia's Dinara Safina also enjoyed a big victory by ousting her fifth-seeded compatriot Anastasia Myskina 6-1 6-3, but as the evening progressed, a majority of the leading players registered victories over lower-ranked opponents.

In the men's draw, top seed Roger Federer struggled to down Belgium's Olivier Rochus 3-6 6-2 7-5, while second seed Rafael Nadal of Spain romped to a 6-1 6-4 victory over American Mardy Fish.

Women's top seed Justine Henin-Hardenne continued her amazing play with a 6-2 6-1 victory over number 14 Ai Sugiyama of Japan, while number three Maria Sharapova overcame Shahar Peer 7-6 6-1.

Just two and half months into her comeback after three years off the WTA Tour, Hingis continued her race towards the top of the rankings, showing the quick footwork and inventive play that once made her world number one.

After the taller and stronger Davenport found the range of her big serve and ground strokes in the second set, the Swiss 25-year-old rapidly regained her edge, moving her opponent around the court and retrieving a succession of heavy shots from behind the baseline.

Hingis broke Davenport three times during the set and won the match when her opponent made a mistake on a backhand volley.

Davenport was clearly struggling with a back injury but still gave credit to her longtime rival.

"I don't want to take everything from her," the American told reporters.

Hingis was thrilled with the victory after going into the match having lost eight of her last 11 meetings with the American.

"To beat Lindsay here in Indian Wells, it probably matters a little bit more than anything else," said Hingis, who faces Safina in the quarterfinals. Slow start

Baghdatis, who lost to Federer in the Australian Open final, is making his Indian Wells debut and he will take on fellow 20-year-old Berdych in the last eight.

The Swiss world number one got off to a slow start against the fleet-footed Rochus, but became much more consistent in the last two sets. "Once you're down a set, you're not allowed to make any more mistakes," Federer said. "I'm relieved I'm through."

Federer will take on another youngster, Richard Gasquet of France, who beat Dominik Hrbaty of Slovakia 6-3 6-4.

Nadal will face Sebastien Grosjean, who beat Xavier Malisse 6-4 6-7 6-2.

Sixth seed Ivan Ljubicic beat Gael Monfils 6-3 6-2 and will play Mario Ancic of Croatia, who took down Paul-Henri Mathieu 7-6(5) 6-3.

Sharapova will play her quarterfinal against seventh seed Anna-Lena Groenefeld, who beat Maret Ani of Estonia 6-1 6-4.

Fourth seed Elena Dementieva beat Na Li China 6-3 6-2 and will face number eight Ana Ivanovic, who trounced Anna Chakvetadze 6-3 6-3.