Sebastien Loeb has moved into the lead of Rally Argentina following a blistering run through the morning loop on Saturday.
Two stalls on the final stage on Friday had left the Frenchman third overnight with a 16 second gap to Dani Sordo in the lead, but four consecutive stage victories enabled him to climb past both second-placed Hirvonen and Sordo into the lead.
Despite a brief scare when he ran off the road briefly on the opening stage of the day, Loeb will now head into the afternoon loop with a lead of some 7.3secs over Hirvonen, who also battled his way ahead of Sordo during the morning stages.
"I've driven as fast as I can but the car was sliding," said Hirvonen. "It's close and there is a good fight ahead this afternoon. I enjoy a good battle but I'd like to be first and not second at the end of it. I will make some changes to the suspension and centre differential settings to improve the handling on some stages, but it will be a compromise as I don't want to ruin the set-up for other tests. The stages aren't as rocky as yesterday. They are narrow and twisty and it's difficult to drive fast, with no room for error."
Running first on the road, Sordo slipped back to third but said he was still happy with the way the day had panned out as he remains in contention, but Petter Solberg lost time with his engine down on power through the high altitude stages. Solberg will now aim to fend off the challenge of Jari-Matti Latvala during the afternoon stages, although the Finn suffered a scare when he lost his bonnet on the first stage of the morning.
“After the first corner of the first stage the bonnet pin came loose and the bonnet started to flap up and down,” he said. “I slowed but realised the stage was long and I could lose a lot of time, so I speeded up again. On the next straight the bonnet came off totally, and flew over the top of the car. We carried on as normal! It has been an OK morning but I'm not here to fight for position, just to finish."
Federico Villagra holds seventh after battling ahead of Matthew Wilson, while Sebastien Ogier is now the lone Citroen Junior Team driver running in ninth after Conrad Rautenbach stopped on SS12.
In the PWRC, Marcos Ligato holds a slender lead over Nasser Al-Attiyah following engine problems for overnight leader Gabriel Pozzo, while Alessandro Bettega is well clear in the JWRC.