Sebastien Ogier kicked off Rally Sweden by establishing a lead of 24 seconds after the three Friday morning stages.
The Frenchman was fastest in all three runs, but claimed the majority of his gap in the third one - despite damaging his car's front by losing control on a water splash.
His closest challenger was Volkswagen teammate Andreas Mikkelsen, who wasn't far off the pace in the first two stages but lost time at the same spot Ogier did in the third test.
The Norwegian was just four seconds ahead of Citroen's Kris Meeke, while top Hyundai driver Dani Sordo held fourth.
Mads Ostberg and Ott Tanak were separated by just 1.3s in fifth and sixth, followed by Hayden Paddon, who is driving the new Hyundai i20 for the first time.
Jari-Matti Latvala was the first driver of the top class to have issues as he suffered a broken driveshaft in the opening stage, which forces him to run in two-wheel drive mode for the rest of the day.
"It happened after a jump before a corner," said Latvala, who is already four minutes behind. "I have no idea why. A mechanical problem I think. Just one of those things."
Hyundai's Thierry Neuville dropped from third place to tenth with transmission troubles in the final run, costing him a minute.
Standings after SS4:
|Pos.||Driver / Co-Driver||Car||Time/Delay|