Argentine Juan Del Potro denied deflated Rafael Nadal a place in a career-first US Open final as he reached his first Grand Slam final, 6-2, 6-2, 6-2 over the Spaniard on Sunday.
Sixth-ranked del Potro took advantage of Nadal's lingering abdominal muscle strain which has bothered him for a month, putting his own huge game into gear for the rapid-fire victory in two hours, 22 minutes.
Del Potro handed Nadal his first straight-sets loss since the 2008 Australian Open semi-finals when Jo-Wilfried Tsonga beat him by a similar margin. He lost in straights in New York six years ago in the second round to Andy Roddick.
Del Potro ended a four-match loss streak to Nadal at Miami last spring and is the only player to have beaten the Spaniard more than once this year.
The victory was the third in a row for the Argentinian in the series with the former number one.