Frenchman Florent Serra withstood 20 aces to upset fourth seeded and two-times finalist Robin Soderling [ Images ] of Sweden 6-4, 6-7, 6-2 in the opening round of the Memphis Championships on Tuesday.

"It's a good victory indoors, (against) one of the best players on indoor courts," Serra told reporters.

"I'm very happy because it's an important tournament here. I have to continue to play like this and play relaxed."

Soderling played with an ailing back and needed a trainer before the start of the third set. The timeout helped Serra calm himself after the second set loss.

"It was a very difficult first-round match for me," Serra said. "He served very, very strong. But I hit the ball very well."

Serra had 12 aces and won 79 per cent of his first serve points to claim the win. He will play Israeli Dudi Sela [ Images ] in the second round. Sela beat American Bobby Reynolds 7-6, 6-2 in the first round Monday.

Second seed Juan Martin Del Potro [ Images ] opened play with a 6-3, 7-6 victory over Argentine compatriot Guillermo Canas [ Images ].

World No. 7 Del Potro won the only break in the fourth game of the opening set. In the second set tiebreak Canas led 3-1 before del Potro won six of the last eight points.

Del Potro recorded 11 aces in the one hour, 41-minute match and won 84 per cent of his second serve points. He will meet Ernests Gulbis [ Images ] of Latvia in the second round.

Gulbis eliminated American Taylor Dent, the 2003 champion, 6-4, 3-6, 6-2.

Top seed Andy Roddick [ Images ] of the U.S. starts his Memphis campaign on Wednesday agains Belgian Steve Darcis.

In women's play, top-seeded Caroline Wozniacki [ Images ] of Denmark ousted Australian Jelena Dokic [ Images ] 6-1, 6-2, hitting nine aces and winning 77 per cent of her first serve points.