Robert Kubica set the pace for Renault in a frenetic final practice session for the Korean Grand Prix ahead of Lewis Hamilton and Fernando Alonso as drivers once again had to contend with a dirty and gripless track.
Organisers oversaw improvements to the inside kerbs at Turns 16 and 18 to try and alleviate some of the issues, but frankly there was little improvement in the levels of adhesion.
The track began the session almost as dusty as it had prior to the first runs on Friday morning and, unsurprisingly perhaps this led to more complaints from drivers over the team radios about heavy graining on the tyres - even those on the harder prime Bridgestones.
Traffic would prove to be an issue too late-on.
The Toro Rossos of Jaime Alguersuari and Sebastien Buemi were first out of the pits, and notwithstanding some brief interference from Adrian Sutil's and Vitantonio Liuzzi's Force India, they remained on the top of the pile for half of the session until the big guns hit the track.
First of those front-runners to emerge were the Ferraris, on hard tyres, and Fernando Alonso was the first to set a quick time - 1m40.795s. Shortly afterwards, Jenson Button, on a six-lap hard-tyre run of his own, went faster by 0.001s.
That stood for all of a minute before Alonso, and then Lewis Hamilton improved significantly, despite running wildly off-track, to lower the mark to 1m39.705s as seemingly every lap saw an improvement.
With ten minutes to go, everyone had completed their hard tyre runs and was back in the pits switching over to the options. This prompted a hectic last few minutes as all 24 runners had a final pop at some qualifying simulation, which saw both Hamilton and Alonso lose time to traffic. The latter incident was particularly bad as the Ferrari driver had to slam on the anchors to avoid hitting Nico Rosberg. The Spaniard did not refrain from showing his emotions with vivid hand gesticulations afterwards.
In the end though it was Renault's Kubica who got the clearest, and fastest run, his 1m37.354s lap good enough to keep him ahead of Hamilton, Alonso and Red Bull's Mark Webber - Sebastian Vettel could only manage 16th as he too ran into problems late-on.
Rosberg, who with a minute to go was second quickest, dropped to fifth ahead of Felipe Massa, Button, Nico Hulkenberg and Michael Schumacher. Sutil completed the top ten.
The German also took the honour for the most dramatic moment of the session when he ran wide at Turn 11 and skidded sideways across the run-off, in doing so throwing up clouds of dust.
Pos Driver Team Time Laps
1. Kubica Renault 1m37.354 15
2. Hamilton McLaren-Mercedes 1m37.402 + 0.048 16
3. Alonso Ferrari 1m37.426 + 0.072 15
4. Webber Red Bull-Renault 1m37.441 + 0.087 13
5. Rosberg Mercedes 1m37.629 + 0.275 12
6. Massa Ferrari 1m37.955 + 0.601 16
7. Button McLaren-Mercedes 1m38.419 + 1.065 15
8. Hulkenberg Williams-Cosworth 1m38.501 + 1.147 17
9. Schumacher Mercedes 1m38.630 + 1.276 12
10. Sutil Force India-Mercedes 1m38.632 + 1.278 18
11. Petrov Renault 1m38.668 + 1.314 14
12. Barrichello Williams-Cosworth 1m38.733 + 1.379 16
13. Buemi Toro Rosso-Ferrari 1m39.058 + 1.704 21
14. Kobayashi Sauber-Ferrari 1m39.145 + 1.791 16
15. Alguersuari Toro Rosso-Ferrari 1m39.159 + 1.805 21
16. Vettel Red Bull-Renault 1m39.780 + 2.426 9
17. Heidfeld Sauber-Ferrari 1m40.289 + 2.935 17
18. Liuzzi Force India-Mercedes 1m41.591 + 4.237 15
19. Trulli Lotus-Cosworth 1m41.623 + 4.269 15
20. Glock Virgin-Cosworth 1m41.853 + 4.499 17
21. Kovalainen Lotus-Cosworth 1m42.095 + 4.741 19
22. di Grassi Virgin-Cosworth 1m43.111 + 5.757 19
23. Senna HRT-Cosworth 1m43.417 + 6.063 19
24. Yamamoto HRT-Cosworth 1m43.880 + 6.526 20
All Timing Unofficial