The Swede, driving a Ford Fiesta R2, ended the opening leg 16.8sec ahead of fellow countryman and championship leader Tom Kristensson.
Rådström notched up four stage wins to pull clear of Kristensson, who stuck with the consistent strategy that has served him well so far this year.
“We have just focused on our job and it seems to have been a good way of thinking. It has been very rough and quite enjoyable also, but there seems to be a big fight for the lead coming up,” said Rådström.
Jan Solans was third, and the only other driver to claim stage victories. The Spaniard was 19.6sec off the lead but had a 12.0sec advantage over Romania’s Raul Badiu. Julius Tannert and Martins Sesks completed the top six.
Sean Johnston was the sole retirement, the American clipping a bank and plunging off the road.