Belgian Thierry Neuville led the Rally of Argentina for Hyundai on Friday after Estonian Ott Tanak suffered a broken driveshaft and spun his Toyota on the last stage of the opening day.
Neuville will start Saturday's second leg with an 11.9 second lead over Citroen's Sebastien Ogier, with Tanak a further 1.5 adrift.
"We didn't really expect to be leading this rally at the end of the first day, especially considering our starting position as first on the road," said Neuville, who won two stages in a wet and muddy day's work.
"It's a pleasant surprise but it has been a complicated day with tricky conditions."
Tanak had led into the day's 23.44km Santa Rosa-San Agustin II special stage near Villa Carlos Paz but spun two km from the finish while Neuville set the pace.
The day's third stage was cancelled for safety reasons due to poor road conditions.
Saturday's leg features a repeated loop of three stages in the pampas and hills of the Punilla Valley, either side of a super special.
The rally is the fifth round of the championship, with Neuville two points ahead of Ogier and Tanak a further three behind.