The Frenchman initially lost his lead on the opening La Bréole - Selonnet stage after rival Yoann Bonato set a blisteringly quick time.
However, Bonato’s rally unravelled on the very next stage when a flat tyre on his C3 cost the Monte expert over two minutes.
Rossel was the fastest of the pair during the last stage and led the category by 2min 00.2sec at the end of the day.
Nicolas Ciamin was another man to drop time on Saturday. Like Bonato, he too picked up a flat tyre on his Citroën during the Saint-Clément - Freissinières speed test and lost almost three minutes.
An impressive recovery drive from Ciamin to win the final stage of the day saw him complete the leg 1min 40.1sec behind Bonato in third.
Austrian driver Hermann Neubauer was 4min28.9sec further back after a consistent day at the wheel of his Ford Fiesta Rally2, whilst Cédric De Cecco rounded out the top five, 2min 45.2sec behind in a Skoda.
Davy Vanneste completed the top six in another C3. With just four stages left to complete on Sunday, the Belgian trails the leaders by 16min 47.8sec.
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