Sebastien Loeb has lost his Rally Australia victory after the three Citroen C4s received one minute penalties for a technical infringement.
The stewards' decision hands the win to Mikko Hirvonen, who therefore extends his championship lead to five points with just two rounds to go.
Loeb's factory teammate Dani Sordo and Citroen Junior driver Sebastien Ogier - who had finished third and fourth - were also given the same penalty for an irregularity in their cars' anti-rollbars.
"The stewards received a post-event scrutineering report from the FIA technical delegate which stated that the front anti roll bar link of car no.1 did not comply with the homologation form of the car," said a statement from the officials.
Loeb had won the event on the road, ending a four-month winless streak and seemingly bringing him back to within one point of Hirvonen in their battle for the title.
With Citroen tipped to dominate the next event in Catalunya, Loeb's victory had put him back in the driving seat in the 2009 title fight, but Hirvonen's increased five point cushion now gives the Ford driver a much better chance of being the first man to beat Loeb to a world championship since Petter Solberg in 2003.
The penalties leave Loeb, Sordo and Ogier in second, third and fifth places respectively, with Jari-Matti Latvala moving up from fifth to fourth in the second Ford.