Teenager Juan Del Potro crushed Andy Roddick 6-1, 7-6 (7/2) to extend his summer win streak to 14 matches in a title victory at the Los Angeles Classic on Sunday.
The world number 24 Argentine repeatedly punished the big serve of the American top seed, leaving Roddick still stranded without a career Los Angeles title - the only US summer trophy he has failed to lift.
Del Potro easily nullified the threat of the Roddick serve, breaking three times in the opening set and allowing the American just four points in the first four games.
The 19-year-old Del Potro has won his last three tournaments, on clay at Stuttgart and Kitzbuehel before stepping onto hardcourt this week for the first time since March.
World number nine Roddick was treated for lower back pain after going down 1-4 as Del Potro claimed only his second career match over a top ten player against 13 losses against the elite.
