America's Robby Ginepri stunned top seed and Robin Soderling 6-4 7-5 in the first round of the Chennai Open in India.

Soderling, 25, who began the year with a first victory over Roger Federer in an exhibition match in Abu Dhabi last week, was knocked out in an hour and 31 minutes.

The Swede began solidly but his game crumbled and he produced far too many errors. Ginepri, pounding away from the baseline, broke in the seventh game and sealed the first set with an ace.

The American lined up three break points in the first game of the second set but Soderling levelled at deuce and came up with two aces to hold serve.

The Swede then broke Ginepri but it was all downhill from there and the American broke back in the eighth and again in the 11th, before serving out for the match.

"It is great to start the year with an important win," said Ginepri.

"Robin has had a fantastic run in the past year and you are never sure what to expect in the first round against a player like him.

"I had to make him move around and make sure that he didn't get a chance to get set."

Soderling conceded he was squarely beaten.

"Everything went wrong for me," he said.

"I wasn't hitting the ball well, I didn't take my chances and he took his.

"It doesn't matter whether you have two break points or three, you still have to take them."

Last year's finalist, India Davis Cup player Somdev Devvarman, stunned veteran Rainer Schuettler 7-5 6-2.

Devvarman had trailed 3-5 in the first set but won six games in a row to gain the edge. He then went 2-0 up in the second and eventually sealed the tie.

In other first-round matches, third seed Stanislas Wawrinka strolled through with a 6-1 6-4 win over India's Rohan Bopanna, Michael Russel defeated home qualifier Prakash Amritraj 6-3 6-1, Slovenia's Lukas Lacko beat Taipei's Lu Yen-Hsun 6-4 6-3 and Holland's Robin Haase beat Yang Tsung-Hua 6-4 6-3.

There were also wins for Germany's Michael Berrer, Israel's Dudi Sela and Kevin Kim of the US.