Kalle Rovanperä held a commanding lead in WRC 2 Pro at Corsica linea - Tour de Corse on Friday after chief rival Lucasz Pieniazek hit trouble in the opening stage.
On his Corsica debut, Skoda Fabia driver Rovanperä ended the leg 2m55.5s ahead of Pieniazek, who lost almost two minutes with a puncture in SS1.
"We made some set-up changes throughout the day and it is now quite good - the car is more enjoyable to drive," said Rovanperä, who is on course to take the championship lead on Sunday.
Pieniazek adopted a cautious approach in his Ford Fiesta for the rest of the day and struggled with pace notes he felt were too slow.
Éric Camilli headed a thrilling two-way battle in WRC 2 after a day-long scrap with fellow Frenchman Yoann Bonato.
Camilli, making his season debut, won all six stages in a VW Polo GTi to end with a 20sec cushion over French rally champion Bonato's Citroën C3.
Russia's Nikolay Gryazin was third in a Škoda Fabia, 22.6sec further back and just 3.6sec ahead of Nicholas Ciamin's Polo in fourth.
Ciamin headed a trio of drivers covered by just 6.3sec. Kajetan Kajetanowicz (Polo) lay 4.8sec back in fifth place, with Fabio Andolfi (Hyundai) 1.5sec adrift in sixth.
Championship leader Ole Christian Veiby was fourth by SS2, but plunged to eighth in SS3 after a puncture cost him 30sec. He recovered to end the leg in seventh position.
Elsewhere, Pierre-Louis Loubet lost more than two minutes with a puncture in SS3. On the retirement list were Nil Solans, who crashed in SS3, Simone Tempestini, who stopped in the same stage with suspension damage and Adrien Formaux who ripped two wheels off his Fiesta in SS4.