Raikkonen was the only man to dip under 1m 19s, with his best time of 1m 18.634s set on Pirelli’s supersoft tyres late in the morning. That put him almost a second clear of the second-placed Red Bull of Max Verstappen.
The Finn was one of four drivers to exceed 100 laps, despite bringing out the red flags briefly when his SF70H stopped on circuit mid afternoon. Verstappen racked up 71 after turbo issues on his RB13’s Renault power unit cost him track time.
A highly productive day for Toro Rosso saw Carlos Sainz take third place after 132 laps in the STR13, whilst a low-key session for Mercedes ended with Valtteri Bottas and Lewis Hamilton fourth and fifth respectively, with 107 laps between them.
Nico Hulkenberg was buoyed by the R.S.17’s performance in his morning outing for Renault - it left the German sixth after 45 laps. Team mate Jolyon Palmer added a further 43 in the afternoon en route to eighth.
Between the yellow cars in the order was Force India’s Sergio Perez, the Mexican putting another 128 laps on the VJM10, whilst Lance Stroll managed 132 for Williams as the Canadian rookie banked some very valuable mileage in ninth.
Romain Grosjean’s running finished slightly early thanks to a water leak on his Haas, putting the Frenchman 10th with 76 laps and prompting him to concede that the team still face 'unknowns' ahead of Australia.
But his misfortune was minor compared to that of McLaren, who endured another session of stoppages, leaving Fernando Alonso 11th after just 43 laps for the day.
Sauber split driving duties, with Marcus Ericsson and Pascal Wehrlein rounding off the timesheet in 12th and 13th respectively, the Swede on 59 laps and the German on 42.