Jari-Matti Latvala heads a Volkswagen 1-2-3 after a dramatic morning in the first full day of Rally Argentina.
Fastest time in a Polo R through the marathon 51.88km stage from Ascochinga to Agua de Oro gave him a 3.3sec advantage as drivers headed into mid-leg service.
Overnight leader Sébastien Ogier was quickest in the opener from Santa Catalina to La Pampa, but lost time sweeping dirt from the driving line in the drier conditions of Ascochinga.
Despite tackling the final 20km of Ascochinga with a power steering problem, Andreas Mikkelsen lies 18.5sec from the lead in third. Fourth is Thierry Neuville, the Belgian unhappy with the grip in his Hyundai i20 and trailing a transmission cover for much of the test.
Kris Meeke’s Citroen DS3 and Martin Prokop’s Ford Fiesta RS complete the top six.
Heavy downpours earlier in the year have left the stages littered with rocks and compressions where the rain washed away the road. Santa Catalina was expected to be the roughest and three frontrunners struck trouble.
Mikko Hirvonen (pictured top) retired his Fiesta RS after hitting a wall while Østberg damaged a front wheel from his Citroen DS3 after striking a rock. A turbo pipe came adrift on Dani Sordo’s i20 and he dropped more than 12 minutes in the two tests.
Nasser Al-Attiyah leads WRC2 in a Fiesta RRC by 5.0sec from Nicolas Fuchs with series leader Yuriy Protasov third.
Ott Tanäk crashed heavily at the same place as Østberg, Jari Ketomaa dropped eight minutes when he stopped to change a puncture and his car would not restart and both Lorenzo Bertelli and Abdulaziz Al-Kuwari stopped.