Nico Rosberg completed the third day of testing for the Mercedes GP team at the Circuit de Catalunya in Barcelona today to bring his pre-season testing programme to its conclusion, completing almost 600kms over 128 laps as he set the fastest time of the day, a 1:20.686, during the driest period this morning.

Cold conditions with patches of intermittent drizzle throughout the morning saw the young German spending the first half of his day working on qualifying simulations and developing the car set-up before completing a race simulation exercise in the afternoon.

"We had a good day today and made some significant progress in terms of set-up which was nice to see. We hadn't got the most out of the car in terms of performance over the last couple of days, but we made a step in the right direction today,” Nico said at the end of the test.

“We went through some big changes this morning step by step and found some good improvements. The longer runs this afternoon were interesting. We learnt a lot as there were other cars running similar programmes at the same time so we were able to do some comparisons. There is still plenty of room to improve but overall we're looking in pretty good shape."

Sebastien Buemi was second fastest overall after the rain altered their plans to repeat Friday’s program of pit stop practice in the morning, followed by a race simulation in the afternoon. While the Toro Rosso team were still able to complete the race simulation, as there were only two periods of light drizzle in the afternoon, pit stop practice was hampered somewhat.

“Despite the rain, my first day in Barcelona has gone well,” commented Sebastien Buemi at the end of the session. “Carrying out a race simulation was very useful and it was particularly interesting to see how the tyre behaviour changed depending on the fuel load. In the races, it will be important to drive smoothly, as on full tanks it is very easy to damage the tyres if you slide too much. Today was good and so we can try and improve a bit more tomorrow, our last chance before Bahrain.”

Jenson Button’s morning session was also affected, limiting the McLaren’s team’s learning of a number of new components. As a result, the morning was spent conducting a number of shorter installation runs to establish set-up. As the track dried over the lunch hour, Jenson was able to complete a race simulation in the afternoon – a run that was only mildly disrupted by late red flags.

This also provided the opportunity for the race team to undertake a series of live pitstops, all of which went without problem.  Today’s long-run times have established a benchmark for the final day of pre-season running tomorrow, which will be carried out by Lewis. He finished third overall after 105 laps were completed.

Rubens Barrichello was fourth fastest for Williams, when, despite the rain, he managed to achieve just over one hundred laps working on race runs and set-up.

“We covered 101 laps today, which is always good. Unfortunately, we had some rain during the day which affected the programme a little bit. Everything that the team has brought to this test seems to be working well, so it’s been a positive day altogether,” Rubens said.

Felipe Massa, driving for the first time this year on this circuit, concentrated mainly on some set-up work and then, in the afternoon, he carried out a race simulation for Ferrari, which was completed successfully. The Brazilian driver drove a total of 115 laps, the quickest in a time of 1.22.344, fifth fastest overall.

Renault’s new Russian racer, Vitaly Petrov was up next completing qualifying simulations and long runs for the French based squad. He managed a total of 68 laps and finished almost two seconds off the pace.

“Another day of changing weather so we lost some time in the morning with the rain, but fortunately it was dry in the afternoon. We had a lot planned as it was my last day in the car before Bahrain and we did some good work and we’ve improved the car quite a bit. The qualifying simulation was useful and it was important I did this before the first race.”

Adrian Sutil replaced Tonio Liuzzi ifor Force India where after a switch to the second race chassis overnight his morning program was principally concentrated on baseline runs and set-up checks. Unfortunately when rain fell mid-morning the team was forced to change its afternoon plans to include performance running rather than a race distance as originally scheduled. Adrian completed just 61 laps as a result, setting the seventh quickest time of the day, a 1:22.606.

“It was OK today but a little disappointing not to have been able to have more running,” he said. “Again we have had rain so we had to wait some time to get some decent running. We only got 61 laps as I was hoping for better weather, particularly after last week's test in Jerez. Tomorrow should be better so that's when the real programme can start for me with a race simulation.

Sebastian Vettel was eighth quickest overall when despite few laps being completed in the morning due to a mixture of rain showers and technical issues, the afternoon session proved more valuable, as the team worked on car set-up for the first race in Bahrain. Sebastian’s fastest time was recorded on his last lap of the day.

“We were late out this morning as we had a few technical issues following the overnight rebuild, which carried over into the planned programme for today,” said Ian Morgan, Head of Race Engineering. “Once we were running in the afternoon we got three or four positive tests completed looking at set-up directions for Bahrain, which gave us some clear results – so we ended the session in much better shape.”

By lunchtime Jarno Trulli had already completed 60 laps in his Lotus and went on consistently throughout the day to finish with a total of 102 laps. The team completed a full race distance and were satisfied with the times and quality of the day’s activity.

“Another productive day with Jarno; over a hundred laps completed with no real mechanical issues and Jarno was able to complete the full race distance in the mix of wet and dry weather,” said Mike Gascoyne, Chief Technical Officer. “We successfully completed our whole program with the changeable conditions and have had two very useful days with Jarno in the car, with a very clear set up direction from him. Now we’re looking forward to further refining the balance of the car with Heikki tomorrow.”

Sauber’s Kamui Kobayashi and Virgin’s Timo Glock rounded out the eleven drivers on track. Winter testing concludes here tomorrow and teams will then begin to pack up for the journey to Bahrain and the season opener in two weeks time.