Poland's Robert Kubica set the fastest time in today morning's final free practice for tomorrow's European Grand Prix.

The 23-year-old BMW Sauber driver recorded a best lap time of one minute and 38.754 seconds to dominate on an overcast morning following heavy overnight rain on the new Valencia street circuit.

In slightly cooler conditions, the drivers were able to set faster times than those yesterday when they were learning the track.

German Nico Rosberg in a Williams was second-fastest, one-tenth of a second behind Kubica, but ahead of third-placed Frenchman Sebastien Bourdais in a Toro Rosso.

Rosberg's Williams teammate Japanese Kazuki Nakajima was fourth.

None of the expected front runners set a time that lifted them into the top four as their teams concentrated on conservation of their tyres for qualifying.

The one hour session on later today will be critical to the outcome of tomorrow's 57-laps race round the 5.42-km Mediterranean harbour circuit.

Brazilian Felipe Massa, in a Ferrari, was the leading driver among the title challengers in fifth place.

Ferrari teammate, defending drivers world champion Finn Kimi Raikkonen, was down in 15th place, one behind compatriot Heikki Kovalainen, winner of the Hungarian Grand Prix three weeks ago, in a McLaren Mercedes.

Drivers championship leader Briton Lewis Hamilton in the second McLaren was content to clock the seventh best time behind German Sebastian Vettel's Toro Rosso.

Two-times world champion Spaniard Fernando Alonso was also among those not pushing for a fastest lap time. He wound up 13th for Renault.

All of the drivers in the top ten clocked times that were faster than that set by Raikkonen when he topped the times in yesterday's second free practice session.