Frenchman Fourmaux dominated Friday's action, leading for most of the day with a composed drive that put him on early the road to what would be a maiden WRC victory. But 3.5 kilometres from the finish of the penultimate stage, a rock impact punctured one of his Hyundai i20 N Rally1’s tyres and handed the lead to a surprised Rovanperä.

“It's just a shame for the puncture. But that's rallying,” said Fourmaux, whose pace had been the standout performance on roads that humbled far more experienced rivals.

Rovanperä inherited first place but made no attempt to hide his struggles on Paraguay's red gravel roads. The two-time world champion ended 7.1sec clear of Fourmaux despite admitting his performance fell well short of expectations.

"We should be a bit faster, and we haven't been the fastest guys today," opined the Finn in a moment of honest reflection. “Position-wise of course it's good, but I cannot say we are really happy about the performance.”

Paraguay’s WRC debut took many by surprise, with savage compressions and constantly changing grip catching crews completely off-guard. The punishment was so severe that Rovanperä joked he could "hear his back cracking" on the landings.

Ott Tänak sat third, just 0.5sec behind Hyundai i20 N Rally1 team-mate Fourmaux. Behind him, Sébastien Ogier provided the day's most remarkable storyline, fighting back from disaster to claim fourth overall. The eight-time champion lost over 30 seconds to a puncture on SS2 but won three stages in an inspired recovery drive that keeps his title hopes alive.

"After the misfortune of this morning, for sure we can be happy with the rest of the day," said Ogier after his stunning fightback.

Championship leader Elfyn Evans began the rally with a three-point lead over Rovanperä but ended 21.1sec back from his Finnish team-mate after suggesting he'd "forgotten how to drive in these conditions".

Defending champion Thierry Neuville struggled in sixth, admitting he was "fighting hard" but unable to find pace or comfort after an overshoot and a spin. He headed M-Sport Ford Puma Rally1 star Josh McErlean, while Sami Pajari dropped to eighth after stopping to change a wheel on SS7.

Takamoto Katsuta was forced to retire his GR Yaris Rally1 after running wide and losing a rear wheel, while Grégoire Munster languished almost 50 minutes back from the lead after going off the road on SS1. Their misfortunes enabled WRC2 hopefuls Yohan Rossel and Nikolay Gryazin to complete the overall top 10.

Rally del Paraguay continues on Saturday where seven stages, totalling 112.78 km against the clock, feature on the itinerary.