Top seed Amelie Mauresmo [ Images ] withdrew from the Stuttgart Grand Prix [ Images ] without playing a match on Thursday, suffering from a right shoulder strain.

The French world number one added her name to a tournament injury list that includes Kim Clijsters [ Images ], Justine Henin-Hardenne and Anastasia Myskina [ Images ], all of whom pulled out before the tournament began.

"On Monday during practice I felt something on the serve, and obviously I was hoping it was nothing too serious, which was not the case," Mauresmo told reporters.

Mauresmo's place in the draw was taken by American lucky loser Lisa Raymond [ Images ], who was beaten 6-4, 6-2 by Michaella Krajicek of the Netherlands. Krajicek next faces Tatiana Golovin [ Images ] of France [ Images ], who beat Czech Iveta Benesova [ Images ] 6-4, 6-3.

The $650,000 event lost another leading player when sixth seed Russian Dinara Safina [ Images ] was upset 6-2, 6-2 by Slovak Daniela Hantuchova [ Images ].

It was Hantuchova's first victory over a top 10 opponent since she defeated Patty Schnyder [ Images ] in Sydney [ Images ] in the second week of the year and follows two previous defeats by Safina, the most recent last week in Luxembourg.

"Even the match last week, I came off the court feeling very well because it was a very good match," said Hantuchova. "There was not much I did wrong, so coming into today's match I felt if I just did a few things better here and there I could take this one."

Fifth seed Schnyder was also stretched before the Swiss left-hander emerged from a two hour 14-minute battle with Israel's Shahar Peer with a 7-6, 2-6, 6-4 victory, clinched on her fifth match point.

Some fine serving played a large part in fourth seeded Russian Nadia Petrova's [ Images ] 6-3, 6-4 win over Anna-Lena Groenefeld of Germany [ Images ].

Petrova, still trying to regain the form that earned her four titles this year before injury stalled her progress, was troubled in a 12-minute opening game in which she fought off four break points, and when she survived three break points when leading 2-1 in the second set.

In the remaining second round match, eighth seed Jelena Jankovic [ Images ] of Serbia hobbled her way to a 4-6, 6-2, 7-5 win over Bulgaria's Tsvetana Pironkova [ Images ].

Fighting off leg cramps in the final set, Jankovic served for the match at 5-2, 5-4 and 6-5 before finally securing a two hour 35-minute victory.