Championship leader Thierry Neuville matched Latvala’s time in his Hyundai, leaving the Belgian nicely poised for an assault on the lead heading into Friday’s opening loop of stages.
Neuville’s main title rivals Sebastien Ogier and Ott Tanak fourth and fifth fastest respectively.
Four-time event winner Ogier lies just 0.4s behind Neuville, with Tanak – who suffered a crash in shakedown earlier in the day – a further 0.2s behind the Frenchman ahead of Friday’s first leg proper.
Neuville’s Hyundai team-mate Andreas Mikkelsen continued his rich vein of form shown last time out in Turkey with the sixth fastest time, a mere 1.7s slower than Lappi’s best effort.
Behind Mikkelsen was the third Hyundai of Hayden Paddon, the Kiwi setting the seventh quickest time ahead of the impressive WRC2 runner Kalle Rovanpera in the Skoda Fabia R5.
Rovanpera set exactly the same time as shakedown pace-setter Teemu Suninen in the M-Sport Ford Fiesta WRC, while Craig Breen was the best of the Citroens in 10th place.
His team-mate Mads Ostberg currently lies 12th fastest, behind WRC2 title contender Pontus Tidemand.
It was a disappointing opening stage for 2017 Rally GB winner Elfyn Evans. The M-Sport driver tied with Ostberg and lie three seconds shy of Lappi.