Kimi Raikkonen posted the fastest time on the penultimate day of this week's testing at Paul Ricard, where teams worked on their preparations for the Canadian Grand Prix.
The circuit was changed from the Monaco to the Montreal-style configuration for today's test, with long straights and tight corners over the 5.2-km 1E layout.
Raikkonen, looking at putting the disappointment of his Spanish GP retirement behind him, took over from teammate Felipe Massa and went quickest with a best lap of 1:28.833 on a day with dark skies threatening rain, which hit the track after lunch and caused a slight delay to the programmes.
The Finnish driver, whose running was limited after being hit by an electronics problem in the morning, finished ahead of a surprising Scott Speed, who made good use of the Ferrari power in his Toro Rosso car to finish only two tenths of a second behind Raikkonen.
Renault's Heikki Kovalainen was third quickest in a closely match field, with less than seven tenths between Raikkonen and eight-placed Pedro de la Rosa.
Australian Mark Webber returned to the cockpit of his Red Bull, replacing teammate David Coulthard, as the team focused on carrying out suspension testing. Webber posted the fifth quickest time of the day, finishing behind Pole Robert Kubica in the BMW Sauber.
Franck Montagny was sixth quickest for Toyota, the Frenchman stopping on track at the end of the day.
"Today was quite okay," said Montagny. "We didn't have a lot of mileage to do and so we tried to optimise the test but it was not easy with the wind conditions and the odd shower of rain.
"We collected some decent information though, working on Montreal set-up and also continuing the step-by-step progress we have made since the start of the year. At the end of the day I had a slight problem and I clipped the outside kerb and stopped. Despite that, I think we made good progress overall."
De la Rosa was unable to keep his McLaren team on top of the times for the third day running after taking over from Lewis Hamilton, the Spaniard posting the eight quickest time.
Rubens Barrichello and Christian Klien shared testing duties for the Honda team, the Brazilian working in the morning and the Austrian in the afternoon. Klien was not very lucky, however, as his engine, an old unit, let go right on his first lap.
Despite some early problems, Barrichello was happy with his day's work.
"I worked on the Canada set-up and in the morning the aero balance was totally wrong but we played with it and we found something which was okay," Barrichello told autosport.com.
"The braking was okay, and I was on the old tyres from yesterday with a lot of fuel so I could have done 1:29 on new a set so it was good."
Briton James Rossiter, in his second day as a test driver for Super Aguri, completed 115 laps on his way to the 10th fastest time of the day.
The Spyker team, using both Christijan Albers and Markus Winkelhock for today's session, finished at the bottom of the times, nearly two seconds off the pace of their closest rival.
Pos Driver Team Time Laps 1. Raikkonen Ferrari (B) 1:28.833 50 2. Speed Toro Rosso-Ferrari (B) 1:29.039 94 3. Kovalainen Renault (B) 1:29.070 89 4. Kubica BMW-Sauber (B) 1:29.157 83 5. Webber Red Bull-Renault (B) 1:29.179 84 6. Montagny Toyota (B) 1:29.205 66 7. Wurz Williams-Toyota (B) 1:29.359 57 8. de la Rosa McLaren-Mercedes (B) 1:29.528 95 9. Barrichello Honda (B) 1:30.108 71 10. Rossiter Super Aguri-Honda (B) 1:30.235 115 11. Klien Honda (B) 1:30.286 25 12. Albers Spyker-Ferrari (B) 1:32.245 16 13. Winkelhock Spyker-Ferrari (B) 1:32.756 43 All Timing Unofficial