Mark Webber claimed day one honours at the Japanese Grand Prix after pacing the second free practice session and, with it, topping the combined timesheets.
The Red Bull man's 1min 32.493secs carved two full seconds off Jenson Button's FP1 time as the sport's two current leading teams swapped places at the head of the field. Lewis Hamilton, not long for McLaren after the six remaining races, was second fastest in the 90-minute session - which was interrupted by an early red flag - with Sebastian Vettel vaulting up the order after a lowly FP1 showing to claim third spot. Webber's advantage over his rivals, having previously topped the times on two occasions, was a couple of tenths, with Hamilton - running a higher downforce spec than team-mate Button - a further tenth clear of the man who inherited his Singapore Grand Prix victory a couple of weeks ago.
Nico Hulkenberg underlined Sahara Force India's recent form by taking fourth on the timesheets, four-tenths off the pace, but there was less good news from the other side of the garage as team-mate Paul di Resta failed to set an FP2 time after crashing out at Spoon in the first few minutes of the session, The Scot held his hands up to a mistake after putting his right-side wheels off the road, but found a couple of mitigating factors in his error by blaming a slowing Kimi Raikkonen and dirt laid down to fill ruts made by previous races. di Resta, who remains - along with his team-mate - at the centre of rumours concerning the second Ferrari seat - found himself 18th on the combined times, based on his FP1 effort.
Ferrari took fifth overall on the day with Fernando Alonso happier with the grip from his F2012 in the later session and, with Felipe Massa remaining in the top ten throughout the day, the Scuderia will hope to be able to take the fight to McLaren and Red Bull in both qualifying and the race as it attempts to keep Alonso at the top of the points table. Alonso, however, continued to struggle with the life of his tyres, as did the two Red Bulls, and it remains to be seen whether changes can be made without compromising performance.
Romain Grosjean boosted Lotus up the order in the second session, taking sixth spot, but team-mate Raikkonen again ran into day one problems, this time of a KERS nature when he was instructed to vacate his cockpit, and wound up down in 14th position, 1.7secs off the pace after completing just a dozen laps.
Behind Grosjean, FP1 pacesetter Button was seventh despite taking over a second off his previous time, while Bruno Senna showed no ill-effects of again handing his car over to Valtteri Bottas in the first session by taking eighth fastest time. Massa was ninth fastest, one place ahead of former team-mate Michael Schumacher, although the German veteran began the run-in to his second retirement with another off, this time copying di Resta's exit at Spoon, albeit without the need for a repeat of the red flags.
The second Mercedes finished eleventh in the hands of Nico Rosberg, despite the German missing much of the early stages after a fresh engine was installed in his W03 following the oil pressure problem that sidelined him late in FP1. Sauber was next up, this time with Sergio Perez marginally ahead of team-mate Kamui Kobayashi, with Pastor Maldonado completing the top 15 behind Raikkonen and ahead of the two Toro Rossos.
Heikki Kovalainen, like Senna, showed that missing FP1 was not necessarily a hindrance, immediately returning to head the 'division three' teams in 18th overall. The Finn, whose future with Caterham remains the subject of speculation, finished a tenth clear of team-mate Vitaly Petrov, although the Russian was prevented from completing the session when his rear wing detached itself at the end of the main straight, sending the CT01 into the gravel trap, fortunately without serious consequences.
Timo Glock again had the upper hand in terms of the Marussia battle, finishing the day half a second clear of team-mate Charles Pic, while Pedro de la Rosa and Narain Karthikeyan brought up the rear, more than five seconds off the pace being set at the front.