Thierry Neuville and Mads Østberg started the day tied at the front after Thursday night’s short curtain-raising speed test at Lousada rallycross circuit.
Hayden Paddon, Jari-Matti Latvala and Kris Meeke all enjoyed a spell at the front before Tänak claimed overnight bragging rights in his Ford Fiesta.
Less than nine seconds covered the leading eight competitors before the rocks and ruts of the final dirt road Ponte de Lima special stage, close to the Spanish border, took a cruel toll on those fighting for the lead.
Paddon’s Hyundai i20 Coupe stopped for the second time with an electrical problem that cost almost 11 minutes, Latvala rolled his Toyota Yaris and conceded nearly five minutes while Meeke broke his Citroën C3’s suspension and retired.
Neuville was delayed for almost 20sec behind the limping Latvala, while a broken front right damper slowed Craig Breen’s C3.
Once the dust settled on Ponte de Lima, Tänak was 3.6sec clear of Sordo, who catapulted from seventh to second amid the drama. Tänak extended his advantage over the Spaniard’s i20 Coupe in the final two street stages in historic Braga.
“We had some damage on the previous stage and it made the car really difficult to drive in Ponte de Lima. At least we’re through and I’m really happy with the day,” said the Estonian.
Breen was 12.9sec off the lead in fourth, 5.4sec clear of Elfyn Evans, who overcame a puncture in his Fiesta. Neuville was sixth, and the Belgian was hoping event stewards would restore some of the seconds lost in Latvala’s dust.
Saturday is the longest of the event. Drivers face two identical loops of three stages north-east of the Matosinhos base, covering 154.56km. It includes the 37.55km Amarante, the longest test of the weekend.
Leaderboard after leg 1:
1. O Tänak / M Jarveöja EST Ford Fiesta 1hr 37min 18.5sec
2. D Sordo / M Marti ESP Hyundai i20 +4.6sec
3. S Ogier / J Ingrassia FRA Ford Fiesta +5.0sec
4. C Breen / S Martin IRE Citroën C3 +12.9sec
5. E Evans / D Barritt GBR Ford Fiesta +18.3sec
6. T Neuville / N Gilsoul BEL Hyundai i20 +22.7sec