Gusting winds and the magic of Federer threw Soderling off course in a first set that flashed by in just 25 minutes.
Soderling won his first game of the contest to hold for 1-1 in the second and by the third set, he had warmed up and fought back from 0-4 down in the tiebreak to snatch it 8-6.
The Swede, who had lost all 11 of his previous encounters against the World No 1, had a set point to stretch the contest into a fifth set but Federer kept his eye on the ball to secure victory.
Federer extended his own incredible record by reaching his 22nd consecutive grand slam semi-final and will take on fourth seed Novak Djokovic for a place in Sunday's showpiece.
Text: Reuters | AP Images
Paes on target for doubles celebration | Full Coverage: US Open 2009