Running in track temperatures between 45 and 47 degrees Celsius, Raikkonen had set the pace from the outset at a warm and dry Sepang, as most drivers ran on the Pirelli supersoft tyres, but his initial 1m 32.665s was later all but matched by Vettel on 1m 32.686s before a revived Lewis Hamilton went quicker still with 1m 32.650s and then 1m 32.539s.
Mercedes had split their set-ups after a lot of overnight cogitation. Hamilton’s car reverted to the proven Singapore set-up, while Valtteri Bottas persevered with a new floor and other changes introduced for the weekend but which had caused problems with the balance yesterday.
Both Ferraris improved on their second runs to go back to first and second, but as Bottas improved from 1m 33.094s to 1m 32.329s, Mercedes were left in a quandary as Hamilton failed to go faster.
The silver cars ended the session fourth and fifth, as Ricciardo’s one-time fastest best of 1m 33.091s left him third for Red Bull.
His team mate Max Verstappen had a more troubled session. The Dutchman ran wide while trying to improve on his run-one best of 1m 32.579s, then had a collision with Jolyon Palmer right at the end in Turn 15 when he turned in as the Briton was thrusting his Renault down the inside on a quick lap. The Red Bull spun, the Renault sustained a broken front wing. It was Palmer’s second incident in the corner, where he’d earlier gone off after his brake pedal went to the floor.
Behind Verstappen in sixth, Sergio Perez eventually got the quicker time for Force India with 1m 33.209s, moving back ahead of team mate Esteban Ocon who had improved to 1m 33.290s. Then they were separated by Felipe Massa who wound his Williams up to 1m 33.240s. Stoffel Vandoorne completed the top 10 in the updated McLaren MCL32, with 1m 33.321s.
Vandoorne’s team mate Fernando Alonso was only 11th, his session including an early spin in Turn 15. Romain Grosjean spun his Haas in his bogey corner, Turn 14, and team mate Kevin Magnussen made it a bad day for the US team with engine trouble. Pierre Gasly also had a tougher introduction to F1, as he struggled with balance issues on his Toro Rosso and was last, more than a second off team mate Carlos Sainz.
The forecast is still for rain in qualifying, which could yet skew things for the race.
WATCH: FP3 action from Malaysia
Unfortunately, we are unable to play the video at this time.
Error Code: UNKNOWN