Sauber's Kamui Kobayashi popped in a controversial 1:19.950 to go quickest in the final moments of testing at Jerez de la Frontera today. Toro Rosso's Sebastien Buemi, who had been the pace-setter for much of the day, finished second quickest ahead of Jenson Button and Nico Hulkenberg.

Conditions were much improved and while the track was still damp this morning following overnight rain this soon dried out thanks to the strong winds and the sun making a number of regular appearances.

Kobayashi was one of five drivers to complete over 100 laps, the Japanese driver enjoying a busy and productive day. His best time was posted right at the end of the day on a low fuel load, having spent much of the session running a much heavier car.

However, one particular team was outraged, claiming that the Sauber driver's time was posted after the session had ended and the lights were red. After thirty minutes of deliberating it was ruled that the time would stand because even though the session had effectively ended the lights at the end of the pitlane were not red at the time.

"It was a good day as we managed to complete our programme," said Giampaolo Dall'Ara. "In the morning we did some aero tests and after the lunch break we concentrated on set-up and tyre evaluation. For most of the day we were running with a high fuel load prior to a run with a lighter car before the end of the session. For tomorrow the weather forecast is not really promising, but we will cope with what we get."

On the agenda for Toro Rosso was an evaluation of a few aero parts, an assessment of different mechanical set-ups and runs with different fuel loads. Sebastien Buemi also tried all three compounds brought here - the soft, medium and hard.

"I am pleased with how the past two days have gone," said the Swiss, "and although rain is never ideal, yesterday's damp conditions meant we could try the wet weather tyres. Today, in the dry, we were able to do a lot of laps, as the car ran reliably. We tried various set-ups and ran with different fuel loads, so we are beginning to get a better understanding of STR5 in general."

Today was the second and final day for Jenson Button as McLaren began the day with a continuation of the early-morning aero mapping it started yesterday. After a successful number of aero runs, the morning's running centred on finding suitable mechanical and aero set-ups.

In the afternoon, the programme focused on longer running, evaluating tyres on a number of varying fuel-loads. At the conclusion of his test, Button declared himself much happier with the seat and installation and was clearly happy with the progress the team is making with the new car despite having made a precautionary stop late in the day when a warning light came on in the cockpit.

Although Nico Hulkenberg finished fourth quickest for Williams, the day was not without its problems, the German suffering a technical fault shortly after the session got underway which compromised his running for much of the morning. Then, in the afternoon, the reigning GP2 champion suffered another technical failure.

"Today was quite a difficult day as we had some technical problems, but I'm still feeling positive about the car," said the German. "Of course, I would like to have had more running time, but that's sometimes the way it goes. Overall, it's been a good two days and the car feels good."