Reigning world champion Sebastian Vettel continues to set the pace in Barcelona, as the Red Bull demonstrates reliability and pace.

With the Austrian outfit's race team personnel present, it aimed to get through simulations of a race weekend P3, qualifying session and a race simulation.

The work went largely to plan as head of race engineering, Ian Morgan, explains: "Generally it was good today and we got through almost everything we wanted to. We had a few small problems, such as an issue with a heat shield. But that's why we do these tests, to iron out any little problems, and generally the simulations went well."

Mark Webber takes over tomorrow, when the team will run a similar programme. "The weather is forecast to deteriorate a bit overnight," said Morgan, "which may make it difficult to run the simulations, but hopefully we can do the same simulations with Mark that we did with Seb today."

Jaime Alguersuari completed his second and final day of testing here, during which he did 97 laps on his way to posting the second quickest time. The Catalan driver had a busy programme, all of which was completed by the time the flag fell. It included a continuation of yesterday's brake system evaluation and an assessment of different set-up configurations to suit various conditions and fuel loads. He also tried three of the four Pirelli compounds - hard, soft and supersoft - again working on car set-up to suit each one.

Once again, Fernando Alonso was at the right end of the timesheets though the Spaniard completed fewer than planned due to a couple of problems, one electrical, the other mechanical, which meant the team did not get through all its planned programme for the day. Despite all this, he still managed to do 90 laps gathering useful data for for the continued development of the F150 and to increase understanding of the Pirelli tyres.

Fourth quickest was Rubens Barrichello in the Williams as the Grove outfit focussed on engine mapping, KERS and reliability. The Brazilian completed 118 laps on his way to posting a 1:24.008.

"We had a very productive day which has helped make up for the time we lost yesterday," said Barrichello. "Today was the first time I was able to use KERS, running with it activated for about 75% of the day so I am feeling happy. We also did some longer runs and I feel we are getting better prepared with everything ready for the start of the season."

"It has been another good day of running concentrating on KERS, setup work, long runs and starts," added Sam Michael, "and we've had no mechanical issues with the Williams Cosworth driveline. Most of the parts on the car now have done quite a few miles so we're pushing into that zone where you can have high mileage failures. We need to do it now though to avoid failures on race weekends. We're learning more about the Pirelli tyres and how to extract the most out of them - there's definitely going to be some tricks to that this year! Right now the rate of performance development is high for all teams, so it's not possible to put any real indicators on pace order."

It was a more productive day for Lotus Renault GP which had Vitaly Petrov on duty in the morning before Nick Heidfeld took over in the afternoon.

The R31 was fitted with some new parts to the water system, which resolved the problems the team experienced in Jerez. The team also logged some useful data from its suspension set-up programme in the afternoon, evaluating changes to the front and rear systems.