Mark Webber set the pace in Saturday's final practice at Suzuka, however, his Red Bull team-mate Seb Vettel did not set a medium tyre lap due to a KERS issue.
First out of the blocks, the two Lotus drivers traded blows at the front with Romain Grosjean leading the way ahead of Kimi Raikkonen while Sergio Perez slotted into third place in his newly built McLaren chassis.
However, as the Red Bulls ventured out it was all change as Mark Webber hit the front with a 1:32.722. His team-mate Sebastian Vettel followed him up the order but only as far as third place with the German reporting to Red Bull that he had flat spotted his tyres. "Not great," is the understatement.
Bigger problems, though, for Nico Hulkenberg who pitted with an issue with his C32's exhaust. He told his Sauber team that "it might be broken" and was soon out of the car.
Back in the action Grosjean hit the front again with a 1:32.707, putting him 0.015s up Webber while Adrian Sutil became the session's first crasher as he lost it at Spoon, went into a spin and tagged the barrier. Game over for the Force India driver.
Vettel soon joined Sutil on the sidelines as, with 20 minutes remaining, his Red Bull racer was in the pits, up on stands and sans bodywork. Minutes later Vettel was seen in jeans and a T-shirt as news filtered through that there was an issue with his KERS battery and that it needed to be changed. As such Vettel did not take part in the medium tyre runs.
That battle was topped by Webber, who clocked a 1:32.053 to beat Lewis Hamilton by 0.134 while Nico Rosberg was third, 0.302s down.
01 Mark Webber Red Bull 1:32.053 17 laps
02 Lewis Hamilton Mercedes 1:32.187 +0.134 18 laps
03 Nico Rosberg Mercedes 1:32.355 +0.302 18 laps
04 Romain Grosjean Lotus 1:32.707 +0.654 26 laps
05 Fernando Alonso Ferrari 1:32.800 +0.747 14 laps
06 Felipe Massa Ferrari 1:32.815 +0.762 14 laps
07 Jenson Button McLaren 1:32.869 +0.816 17 laps
08 Kimi Raikkonen Lotus 1:32.946 +0.893 25 laps
09 Sebastian Vettel Red Bull 1:33.036 +0.983 8 laps
10 Nico Hulkenberg Sauber 1:33.076 +1.023 12 laps
11 Sergio Perez McLaren 1:33.158 +1.105 15 laps
12 Jean-Eric Vergne Toro Rosso 1:33.260 +1.207 15 laps
13 Daniel Ricciardo Toro Rosso 1:33.490 +1.437 16 laps
14 Pastor Maldonado Williams 1:33.638 +1.585 17 laps
15 Paul di Resta Force India 1:33.660 +1.607 19 laps
16 Esteban Gutierrez Sauber 1:33.732 +1.679 15 laps
17 Valtteri Bottas Williams 1:33.955 +1.902 18 laps
18 Adrian Sutil Force India 1:34.773 +2.720 8 laps
19 Giedo van der Garde Caterham 1:35.473 +3.420 20 laps
20 Charles Pic Caterham 1:35.518 +3.465 18 laps
21 Max Chilton Marussia 1:35.844 +3.791 16 laps
22 Jules Bianchi Marussia 1:39.378 +7.325 20 laps