Eight-time world champion Sebastien Loeb saw his lead in the Rally of Argentina - the event he has won for the last six years - slashed to just 0.1sec.
Loeb's Citroen teammate Mikko Hirvonen put in a blistering performance on the day's sixth and last stage to edge the Frenchman by 1.0sec after being down by 1.1sec at the end of the fifth stage.
"The start of the stage was not good at all but the rest was okay so we will see what happens," said Hirvonen. "I hope we will have a bit of a fight because Dani (Sordo) in third is not so far away."
Sordo, in a factory Ford Focus, was third quickest on the final stage, 21.0sec adrift of Hirvonen.
Loeb admitted it hadn't been an easy stage.
"The visibility was coming down and I lost a bit of confidence because it was very slippery in some places, not easy," he said.
Qatar's Nasser Al-Attiyah set the fourth fastest time ahead of Mads Ostberg and Martin Prokop.
Loeb had been 13.4sec faster than Hirvonen on the fifth and penultimate run of the day while Sordo was in third, 13.1sec down on the French driver at that stage.
Norway's 2003 world champion Petter Solberg, in a Ford Fiesta, had led after three of the day's six stages.
But his hopes were shattered when he failed to start the fifth stage after the steering arm on his Fiesta broke when he was 5.8km from the end of stage four.