Lewis Hamilton set a surprise fastest time for McLaren at the end of Friday practice for the German Grand Prix at the Nurburgring.
In a mostly dry session under ominous skies, Hamilton managed to beat Red Bull's Sebastian Vettel by 0.182 seconds, with championship leader Jenson Button third.
In a repeat of first practice, the early running was interrupted by a brief shower, which meant a quiet half hour before dry weather tyres could be used.
Vettel had managed to get a quick lap in before the rain - despite a near-miss with Sebastien Bourdais at the first corner, but once the conditions had cleared Heikki Kovalainen, Nick Heidfeld and Webber all took turns on top, the latter using the softer tyres.
Another Brawn versus Red Bull battle then developed as Button beat Webber's time just before the one hour mark, and ten minutes later Vettel hit the front - using super soft tyres like his rivals with a 1m32.342s, 0.027s quicker than Button.
By now the skies had darkened again and light drizzle was falling. This caught Hamilton out, the world champion spinning at the second corner, but he recovered quickly and set the fastest time of the afternoon on his next lap.
Vettel remained second, with Button sandwiched between the Red Bulls in third.
Jarno Trulli also had a spin in the opening complex, before taking fifth place.
It was another excellent session for Force India as Adrian Sutil recovered from his morning glitch to take sixth. But this time it was Giancarlo Fisichella who was in trouble - the Italian spinning and damaged his car on the barriers just as the early shower hit.
Rubens Barrichello took seventh in second Brawn, with Renault's Fernando Alonso and Nelson Piquet eighth and 10th, split by Williams's Kazuki Nakajima, although Piquet ended the session parked on the grass after an electrical problem on his last lap.
Ferrari slipped back after its strong morning, with Felipe Massa the best of its drivers in 12th.
Heikki Kovalainen was unable to match his McLaren team-mate Hamilton's strong late run, taking to the grass on his final lap and ending up 17th.
Pos Driver Team Time Laps
1. Hamilton McLaren-Mercedes (B) 1:32.149 23
2. Vettel Red Bull-Renault (B) 1:32.331 + 0.182 31
3. Button Brawn-Mercedes (B) 1:32.369 + 0.220 32
4. Webber Red Bull-Renault (B) 1:32.480 + 0.331 28
5. Trulli Toyota (B) 1:32.511 + 0.362 32
6. Sutil Force India-Mercedes (B) 1:32.585 + 0.436 32
7. Barrichello Brawn-Mercedes (B) 1:32.664 + 0.515 26
8. Alonso Renault (B) 1:32.774 + 0.625 24
9. Nakajima Williams-Toyota (B) 1:32.872 + 0.723 32
10. Piquet Renault (B) 1:32.992 + 0.843 29
11. Heidfeld BMW-Sauber (B) 1:33.012 + 0.863 36
12. Massa Ferrari (B) 1:33.052 + 0.903 34
13. Rosberg Williams-Toyota (B) 1:33.128 + 0.979 34
14. Kubica BMW-Sauber (B) 1:33.161 + 1.012 28
15. Glock Toyota (B) 1:33.172 + 1.023 34
16. Raikkonen Ferrari (B) 1:33.182 + 1.033 29
17. Kovalainen McLaren-Mercedes (B) 1:33.724 + 1.575 27
18. Buemi Toro Rosso-Ferrari (B) 1:33.903 + 1.754 30
19. Bourdais Toro Rosso-Ferrari (B) 1:34.025 + 1.876 30
20. Fisichella Force India-Mercedes (B) 1:38.877 + 6.728 3
All Timing Unofficial