Belgium - Australian Mark Webber topped the times in Saturday morning's final practice ahead of qualifying for Sunday's Belgian Grand Prix.
The 34-year-old Red Bull driver and championship leader posted a time of one minute 46.106 seconds midway through the session before rain arrived and disrupted the running.
Briton Lewis Hamilton of McLaren was second quickest ahead of German Sebastian Vettel in the second Red Bull as no more than three tenths of a second separated the top three drivers.
An air-box failure caused Vettel to stop at the entry to the pit lane just as the rain arrived, but the 23-year-old's car was up and running again before the end of the session.
Briton Jenson Button was fourth quickest in the second McLaren ahead of Pole Robert Kubica of Renault, fifth.
Double champion Spaniard Fernando Alonso was sixth fastest followed by his Ferrari team-mate Brazilian Felipe Massa.
Adrian Sutil made it into the top ten again for Force India ahead of fellow German Nico Hulkenberg of Williams and Japanese Kamui Kobayashi of Sauber.