ISTANBUL, May 9, 2008 (AFP) - Defending drivers world champion Kimi Raikkonen topped the times in Friday´s afternoon practice for Sunday´s Turkish Grand Prix but rued the amount of time he lost with problems during the morning.

"That was not the best of Fridays," said Raikkonen, who finished at the bottom of the timesheets in the morning after being hit by a gearbox problem.

"This morning, I only managed one timed lap before a gearbox problem meant I could not go out for the rest of the session. In the afternoon, I struggled a bit to find the right settings on the car.

"One of the main problems today was getting the tyres up to the correct temperature, but I think that tomorrow, partly as the grip level on the track improves and partly as we work to improve the set-up, it will be a different situation.

"We lost valuable time this morning, but we still have enough data to analyse so that we can be ready to tackle the rest of the weekend."

Raikkonen leads the title race by nine points after the first four races of the season.

Briton Lewis Hamilton, who is second in the championship, finished just behind the Finn with a time that was only just 0.036 seconds slower.

Raikkonen´s Ferrari team-mate Felipe Massa, chasing a Turkish hat-trick after winning from pole position at Istanbul for the past two years, was quickest in the morning, but only third fastest in the afternoon.

"Overall, this was a positive day," he said. "The track is very fast, even if it´s still a bit dirty, which meant it was quite easy to make mistakes.

"The low temperatures mean it is difficult to get the most out of the tyres on a first timed lap, especially on the harder ones.

"We tried various settings and now we need to look at the data from everything we have done over these three hours, to be as well prepared as possible.

"I feel comfortable on this track and I think I can be very competitive tomorrow and on Sunday in the race: it would be fantastic to win again here, after having done it for the past two years."