Double runs of Laukaa and Lankamaa - which was sadly cancelled for the second pass - north of host city Jyväskyla were punctuated by service, with a short sprint through the mixed-surface Harju test marking the midpoint of the leg.
Hyundai i20 N star Tänak was immediately on a charge and moved into the lead in the first stage when he outpaced closest challenger Esapekka Lappi by 2.7sec.
Lappi pulled back three-tenths of a second over the legendary 21.69km Lankamaa blast but was unable to make any further inroads as Tänak charged clear. The pair were split by 6.2sec with four more special stages remaining today.
Tänak was surprised to find himself ahead of the field and complained of handling issues throughout the morning. The Estonian admitted he was having to take risks and even said his hands were shaking at the end of SS4.
“The car is fast, but the relationship between the car and driver isn’t giving much feedback and I don’t really feel what I am doing,” he said. “When I put in some steering input or under braking, the feedback is not coming - especially when I am on the limit.”
“This is Finland - we need to drive. Of course I want to win, but we need to be realistic and it’s only the start of the rally.”
Elfyn Evans completed the leading trio 4.9sec behind Toyota GR Yaris team-mate Lappi. The Welshman had a clean run but, so far, has been unable to replicate the pace which saw him take victory here last year.
Craig Breen’s only bump in the road was a faulty intercom in the first stage which meant he could only hear co-driver Paul Nagle through one ear. The M-Sport Ford Puma driver was just 2.4sec adrift of the podium and held 1.8sec in hand over championship leader Kalle Rovanperä, who lacked traction running first on the road.
VIDEO: Solberg rolls out in Finland
Traction was also at a premium for Thierry Neuville, who dropped to seventh overall despite leading after Thursday night’s super special. He was visibly frustrated at the end of stages but vowed to work with his Hyundai team to improve the car.
M-Sport Ford youngsters Pierre-Louis Loubet, Jari Huttunen and Gus Sreensmith rounded off the leaderboard.
Adrien Fourmaux languishes well down the order after making stage-side steering repairs when he hit a rock hidden inside a corner on SS2. The Frenchman also suffered an unrelated power steering failure one stage later.
"I had nothing in my pace notes to say there was anything in the cut," he explained. "We had to fix a bolt in the steering arm and we used some cable ties to make sure it was tight."
Oliver Solberg was the first major retirement and rolled his Hyundai on the very first corner of the day's opening stage. Roll cage damage means he will not restart on Saturday.
- Full coverage from Secto Rally Finland is 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.