Lewis Hamilton set the fastest time in an action-packed second practice session at the Japanese Grand Prix as the Suzuka circuit bit back. Nico Rosberg was second fastest and 0.240s off his Mercedes team-mate and championship rival, but it was the one-second gap to Valtteri Bottas in third that underlined the dominance of Mercedes at Suzuka this year. Jenson Button was fourth in the McLaren ahead of Sebastian Vettel's Red Bull, the highest-placed non-Mercedes-powered car. Kimi Raikkonen was sixth fastest ahead of Ferrari team-mate Fernando Alonso, with Kevin Magnussen eighth and Daniil Kvyat ninth. After a fairly uneventful first practice session, three drivers made mistakes as the circuit lived up to its reputation as one of the most demanding on the calendar. Home hero Kamui Kobayashi was the first to hit the barriers after a snap of oversteer at the start of the Esses spat him off the track and backwards across the gravel. Damage to the front wing and rear of the car will only add to the headaches Caterham is facing this weekend. Daniel Ricciardo then lost his Red Bull on the exit of the final chicane in an unusual accident that saw him plough head-on into the barrier. Fortunately he was able to lock a brake and shed some speed, meaning the impact with the barrier, which caused Timo Glock a back injury back in 2009, was not to heavy and he walked away unaided. The car had to be lifted to the inside of the track, causing a brief red flag after 30 minutes of running. Esteban Gutierrez was involved in the last of the three accidents when he lost his Sauber at Spoon and crashed into the barrier. A second red flag came just minutes before the end of the session when Jean-Eric Vergne pulled up in his Toro Rosso on the straight between Spoon and 130R. It was the second time he stopped during the session, and the third time his car stopped on Friday after Max Verstappen's engine troubles in FP1.