On a slightly shortened Friday at the Mediterranean island event, Pajari repeatedly punched in top-three stage times aboard a Toksport-prepared Škoda Fabia RS Rally2.
His breakthrough finally arrived in the day-ending Monte Lerno test where an inch-perfect drive vaulted the Finn from fourth to first. In doing so he surpassed Teemu Suninen, who encountered tyre damage, to claim the top spot.
Outpacing nearest overall challenger Adrien Fourmaux by 17.0sec in the stage, Pajari heads the Ford Fiesta Rally2 man by 6.3sec ahead of Saturday's penultimate leg.
Pajari’s team-mate Andreas Mikkelsen completed the podium despite nursing an early-morning puncture. The Norwegian, who is only contesting selected rallies this season, trailed Fourmaux by 9.6sec, with fourth-placed Miko Marczyk almost a minute further back.
Series leader Yohan Rossel struggled to find a rhythm aboard his Citroën C3 Rally2 and ended the day down in fifth overall. A stroke of luck came his way, however, as his primary title rival Oliver Solberg leaked significant time with damaged suspension.
Kajetan Kajetanowicz holds sixth while Suninen, who led before SS7, is seventh.