Lewis Hamilton completed a clean sweep of practice sessions for the Japanese Grand Prix but saw his advantage cut by Sebastian Vettel in a session ended by a crash for Nico Hulkenberg.
In a disjointed session that started in drizzle, was interrupted by rain and ended in bright sunshine, Hamilton posted a 1m29.599s on the supersoft compound tire to lead Vettel by just 0.116s. It marked a much more competitive session for Ferrari after being 0.8s off the pace on Friday, but the overall times were over a second slower than in FP2 due to the changeable conditions.
Ferrari led the way early on as light rain fell, with wind posing more of a challenge to the drivers as a number of cars got out of shape courtesy of a tailwind through the Esses. After the rain intensified and saw a 20-minute spell with little running, the track quickly dried in the second half of the session, but the wind remained tricky.
Kimi Raikkonen was third quickest but ran wide at Turn 7 — toward the end of the Esses — and did well to catch the car as it slid through the gravel before reaching the barrier. The Finn was just under half a second off Hamilton as the championship leader appeared to struggle early on, and Ferrari will hope for continued mixed conditions in qualifying to stay close to Mercedes.
Aside from Raikkonen’s off, Sergio Perez went wide at Spoon and then Charles Leclerc followed a slight error at Degner 2 with a similar trip into the run-off area as Perez, before Hulkenberg brought out the red flags.
In a moment that was similar to Fernando Alonso early in the session, Hulkenberg got slightly wide on the exit of the first right-hander through the Esses. While Alonso managed to catch his McLaren, Hulkenberg overcorrected as the rear stepped out and slid backward into the barrier on the outside of the next corner, heavily damaging the rear end of his car.
That crash came with three minutes remaining on the clock and meant the session ended under red flags, with Max Verstappen finishing 0.7s adrift of Hamilton in fourth and just over 0.1s clear of Valtteri Bottas and Daniel Ricciardo.
The Force Indias continued their strong form with Esteban Ocon and Sergio Perez seventh and eighth respectively, ahead of Carlos Sainz and Kevin Magnussen.
Pierre Gasly ended up slowest for Toro Rosso after complaining of oscillations with the updated Honda power unit, having already missed most of FP2 with a fuel cell issue on Friday.