Sebastien Ogier claimed four stage wins to extend his Rally Mexico lead to over 35 seconds heading into the final leg on Sunday.
The reigning champion began the day sitting in fifth place but made progress thanks to an impressive pace and some good fortune as others hit trouble.
Friday leaders Dani Sordo and Sebastien Loeb both suffered punctures on SS14 (Guanajuatito 2) which dropped the pair out of realistic contention.
Loeb had to stop to replace his front left tyre during the stage, after hitting a rock mid-way through, losing over two minutes to Ogier.
Sordo fared marginally better, ceding 30 seconds with the Spaniard now third behind Kris Meeke.
The stages were a gruelling and rocky test of man and machine, with neither coping particularly well in the searing Mexican daytime heat.
Errant stones first halted Loeb's Citroen as the Frenchman looked set to build on his overall lead, before Sordo's Hyundai also fell foul of the precariously placed obstacles on the stage.
Ogier's progress up the order began in the opening pass through Guanajuatito when Toyota Gazoo Racing's Ott Tanak suffered a turbo failure and was forced to retire for the day.
The Estonian had been the only Toyota still in the hunt for a podium after engine overheating issues dogged team-mates Jari-Matti Latvala and Esapekka Lappi on Friday.
Having jumped ahead of Loeb and Sordo following their misfortunes, Ogier then catapulted his M-Sport Ford Fiesta WRC into the lead after Meeke endured a stall on SS13 (El Brinco) and a spin on SS15 (Otates 2).
Meeke exchanged stage wins with Sordo in the Super Special at the Leon Autodroma and remains Ogier's nearest rival in second place, albeit 35.9 seconds in arrear with just three stages to go.
Despite Sordo's strong showing, Hyundai had another disappointing day with both Andreas Mikkelsen and Thierry Neuville lacking pace.
First on the road all day, Neuville lost another minute in the morning's opening stage when his car cut out following a water splash.
The Belgian then suffered two punctures of his own but is set to pick up points for fifth, one place behind Mikkelsen.
Story by Stephen Brunsdon