VIENNA, Austria — Andy Roddick was taken to five sets by Jurgen Melzer on slow indoor clay today, giving the defending champion United States a 1-0 lead over Austria in the first round of the Davis Cup.

Roddick struggled to find his rhythm in beating his 57th-ranked opponent 6-4, 4-6, 6-3, 6-7 (4), 6-3. Melzer, who was treated for a thigh injury in the fifth set, varied his game with drop shots from the baseline and unpredictable charges to the net.

Roddick was irritated by the crowd of about 5,000 that often shouted between his first and second serves. The sixth-ranked American hadn't previously dropped a set to Melzer and extended his career record against the Austrian to 7-0. Roddick closed the match with his 20th ace.

James Blake played Stefan Koubek in the second singles Friday on the opening day of the best-of-five series.

The United States won its record 32nd Davis Cup title in December. Austria has not won a World Group series since 1995.

Roddick faced four break points in the opening game. He served three aces to hold before immediately breaking the Austrian. While serving for the set at 5-3, Roddick double-faulted and then netted a backhand to let Melzer back in. But he converted his first set point on Melzer's serve.

Roddick saved two break points in the opening game of the second set before dropping his next service game at love when he netted a forehand. The set then went with serve to even the match.

Melzer took an early lead in the third set as Roddick dropped serve twice. But the American recovered and won nine of the next 12 games to take the set and go up 4-2 in the fourth. Melzer tied it at 4-4 when Roddick hit a forehand long. The Austrian missed a set point at 6-5 but won the tiebreaker.

In the fifth set, Melzer hit a forehand pass to break in the first game before Roddick won the next four. Down 4-2, Melzer received treatment for a right thigh injury and didn't win a point against Roddick's serve after that.