LOS ANGELES, Aug 11: Argentine teenager Juan Martin Del Potro upset top seed Andy Roddick 6-1, 7-6 on Sunday to win the ATP event in Los Angeles and claim his third successive title.

In his first final on hard courts Del Potro, 19, produced a brilliant and mature performance, rocketing winners past the American for his 14th consecutive victory.

Roddick, who had treatment on a lower back injury midway through the first set, was thoroughly outplayed in the early games and Del Potro held on in the second to complete victory without losing a set in the entire tournament.

In perfect conditions, Roddick looked shell-shocked as Del Potro, with his forehand working to perfection, ripped through the first four games for the loss of just four points.

In the fifth game, the American received a warning for throwing his racket and then called the trainer for treatment on his back.

When he returned, Del Potro held serve and then broke Roddick for the second time thanks to a flashing forehand pass to seal the set.

Roddick tried to vary his attack in the second set with the occasional serve and volley.

He stayed on track with the Argentine but could not force a single break point on the Del Potro serve and the set headed to a tiebreak.

Points went with serve until an errant Roddick forehand gave Del Potro a 4-2 lead and he then won the next three points to clinch the title when Roddick sent a forehand long.

The win was Del Potro’s first against a top-10 player in 14 attempts.—Reuters