HOUSTON — Third-seeded Mardy Fish beat Germany's Rainer Schuettler 7-6 (4), 6-3 in a first-round match today at the U.S. Clay Court Championship.

Fish broke serve early in the final set when Schuettler double-faulted and netted a backhand to put the American up 2-0. He needed just five or fewer points to hold his own serve the rest of the match.

Fish set up triple match point at 40-love against the world's No. 87 player with a blistering forehand down the line for a winner. He closed the match out two points later with an ace. Fish finished with 11 aces to two for Schuettler.

It was the third win for the world's No. 42 over Schuettler, who has beaten Fish only once — in the quarterfinals at the Australian Open in 2003 when the German was ranked as high as No. 6 in the world.

"He's a dangerous player because he can at will just put on the clamps and not miss and just run anything down and just be a nuisance to his opponent," Fish said. "I knew that going in. Clay was going to be a pretty tough surface to play him on for me. It was a nice win, for sure."

It was Fish's first clay court match of 2008. Last week he practiced at some clay courts at a park in North Carolina where he went to cheer on his Davis Cup teammates, who beat France 4-1.

But the clay there was faster, so Tuesday's match was a tough adjustment, he said.

The two players slugged through the tiebreaker, with Fish pulling off a stunning forehand half-volley winner after Schuettler hit a sharply angled passing shot to earn the American a set point. The German dumped a forehand return of serve into the net to give Fish the tiebreaker, 7-4.

Earlier Tuesday, fifth-seeded Agustin Calleri of Argentina beat American Vincent Spadea 6-4, 6-3 in a first-round match. Spadea double-faulted to give the South American two match points. Calleria got to double match point and went on to win the game, breaking Spadea's serve when he hit a forehand long.

In another first-round match, Sergio Roitman of Argentina outlasted American John Isner 3-6, 7-6 (6), 6-3.

Second seed Tommy Haas, No. 36 in the world, was scheduled to play the lone singles match Tuesday night against Russia's Igor Kunitsyn.