The Norwegian headed Bolivian youngster Marco Bulacia by 4min 37.7sec. Gus Greensmith was third after failing to complete a tough day on wet and muddy gravel roads in Cordoba province.
Østberg quickly overhauled Greensmith, who led after last night’s short opening speed test in Villa Carlos Paz, and built a 20sec advantage. The Norwegian’s task was eased when Greensmith retired his Ford Fiesta with broken front suspension in the afternoon.
Despite a front right puncture on his Citroën C3, Østberg preserved his comfortable advantage over Bulacia, who won all three afternoon stages.
His hopes took a knock this morning when he punctured a tyre on his Skoda Fabia R5 and stopped to replace it. Bizarrely, he replaced the wrong wheel and had to stop again later in the test for a second change.
Pedro Heller topped WRC 2 by almost six minutes after a day of attrition in which the lead changed hands on five occasions.
Kajetan Kajetanowicz relegated overnight leader Takamoto Katsuta early this morning but the Pole retired his Volkswagen Polo with broken rear suspension after landing heavily over a jump.
Katsuta regained the initiative only to lose it again to Chile’s Alberto Heller this afternoon. Alberto Heller stopped in the penultimate test when his Fiesta’s engine auxiliary belt broke and Katsuta was back in front for a third time.
There was final stage heartbreak for the Japanese youngster when a puncture and broken wheel rim deposited his Fiesta into a ditch and he retired.
Pedro Heller was left with a 5min 42.1sec lead over Brazilian Paolo Nobre, with Benito Guerra 26.6sec back in third, despite rolling his Fabia this morning. Katsuta, Alberto Heller and Kajetanowicz completed the top six after their retirement penalties.