Belgian holds 0.7s lead over Welshman with Ogier 19.4s back in third place.
Thierry Neuville bounced back from a frustrating opening to demote early pacesetter Elfyn Evans and grab a slender lead in the RallyRACC - Rally de España on Friday.
Neuville wrestled handling problems with his Hyundai i20 throughout the morning's three smooth asphalt speed tests in the Costa Daurada hills. Set-up changes at the mid-leg service transformed his confidence and he ended with a 0.7sec advantage over Evans.
Evans is the only driver who can deny Sébastien Ogier an eighth world crown in nine seasons and he ended 18.7sec clear of the Frenchman after six flowing tests near Salou.
Evans, driving a Toyota Yaris, dominated the morning. He won all three special stages, one shared with Neuville, to build a 7.9sec lead over the Belgian. A rejuvenated Neuville responded with a treble of his own when the stages were repeated this afternoon.
"We struggled with understeer this morning and were trying to solve it for this afternoon," explained Neuville. "We made a good step and that was why we were able to go faster, but we want to make another step tomorrow because I feel there's more to take out of the car and ourselves."
Evans was disappointed to concede the lead, but relieved to survive a hefty slide into a kerbstone this afternoon. "It was a bit lucky. I hit the rear fairly hard on what was a sloped kerb, thankfully, and we got away with it," he said.
Ogier, who will lift the title if he outscores Evans by seven points, could do nothing about the battling duo ahead. He lacked confidence in his Yaris and had his hands full in fending off home hero Dani Sordo, who ended 5.4sec behind in an i20.
Kalle Rovanperä initially struggled to understand the characteristics of Pirelli's new P Zero hard compound tyres, which were being used for the first time. Driving a Yaris, his pace improved significantly in the afternoon and he was fifth, 13.2sec adrift of Sordo. M-Sport Ford Fiesta duo Adrien Fourmaux was a distant sixth.
It was a disastrous morning for Takamoto Katsuta who slammed his Yaris into a roadside barrier in the opening stage after misunderstanding a pace note. He limped to the finish with heavy damage to the front left suspension and retired.
Also on the sidelines was Ott Tänak, who retired after damaging his i20’s rear suspension when he went off the road in the afternoon's opening test when lying sixth.
Saturday's leg is the longest of the event, containing 117.54km of competition across seven stages. Three tests are driven twice either side of service before the day closes with a spectacular seafront stage in Salou.
Leading positions after Friday
1. T Neuville / M Wydaeghe BEL Hyundai i20 1hr 01min 26.6sec
2. E Evans / S Martin GBR Toyota Yaris +0.7sec
3. S Ogier / J Ingrassia FRA Toyota Yaris +19.4sec
4. D Sordo / C Carrera ESP Hyundai i20 +24.8sec
5. K Rovanperä / J Halttunen FIN Toyota Yaris +38.0sec
6. A Fourmaux / A Coria FRA Ford Fiesta +1min 10.2sec