Huge compressions, endless twists and turns and loose gravel provided a tough challenge for crews, but the Spaniard stayed on track to open a 17.4sec advantage in his Hyundai i20 after six stages in northern Sardinia.
M-Sport Ford man Teemu Suninen was second in his Ford Fiesta, followed by title challenger Thierry Neuville, a further 17.8sec behind in another i20.
Sordo, competing in his first WRC event since March’s fixture in Mexico, opted to take five medium compound tyres aboard his Hyundai for both loops. As the times rolled in, it was clear the Spaniard’s decision had paid off as he claimed four stage wins.
“Of course I am really happy to come back like this. We always say that road position is very important here and we had a really good one today, but at the same time we pushed hard and made time with good tyre choices,” said the rally leader.
Suninen’s day got off to a flying start. The Finn snatched a surprise lead in the rally-opening Tempio Pausania speed test, his time a whopping 12.4sec clear of the rest of the field.
However, he was unable to match Sordo’s pace on the day’s remaining tests and his decision to carry two hard compound tyres for the final loop didn’t go the right way.
“It was a silly mistake for us to take two hard tyres. We expected to see an increase in road temperatures, but when we got there it was fully in shadow so we didn't get any grip advantages,” he explained.
Neuville had his own issues to contend with. After struggling with the set-up of his Hyundai, two stalls followed, and valuable time was kissed goodbye as he struggled to get the car restarted. He holds third, 35.2sec adrift of his leading team-mate.
Sébastien Ogier rounded out Friday’s opening leg 0.8 sec behind his title rival in fourth, followed by Toyota Yaris team-mate Elfyn Evans who was 15.9sec further back. Running first and second on the road respectively and with no clean line to follow, both struggled to find traction.
Gus Greensmith continued to show potential with a consistent run over Friday’s relentless stages. The Englishman brought his Fiesta back to service in sixth, trailing the leading pace by 01min07.1sec.
Pierre-Louis Loubet was 26.4sec behind in seventh. The Frenchman was lucky to finish after bending the rear wheel of his privately-entered i20 in the penultimate stage.
Ott Tänak’s championship hopes were dealt a heavy blow when his Hyundai picked up a suspension issue in the opening stage. He was forced to limp through the following three stages before a repair could be made in service, dropping almost two minutes. He ended eighth.
Video: Rally Italia Sardegna - SS4 - SS6
Kalle Rovanperä also endured a frustrating Friday. The 20-year-old was sixth before his Yaris picked up a steering issue in the penultimate speed test, plunging him down to ninth. Oliver Solberg completed the top 10 in his Skoda Fabia Rally2 and led the WRC 3 field.
Esapekka Lappi pulled over in SS2 with an engine issue on his Fiesta. It proved terminal and the M-Sport Ford team has confirmed the Finn will not restart on Saturday. Japanese hotshot Takamoto Katsuta also took an early bath after going off the road when he overcooked a tightening right-hander. He is expected to restart tomorrow.
Saturday is the longest leg of the weekend, with 101.69km of flat-out action tightly packed into six daunting tests. Service in Alghero after the fourth stage of the day will be the only respite for crews.
• Full coverage from Rally Italia Sardegna will be available on WRC+ All Live here, including every stage broadcast as it happens as well as key interviews, features and expert analysis from the service park.