Despite withdrawing from last week's test, Lotus was straight back on the pace at Barcelona today, Romain Grosjean edging out Jenson Button and Sergio Perez to top the timesheets.

"Our main target for today was to compress as much set-up work as we could into the first day as we are playing catch-up relative to our rivals at this track," said Lotus technical director, James Allison. "Of course, we want to complete as many laps as possible, but this second objective is inevitably compromised somewhat by needing to make many short runs punctuated by set-up changes."

"Obviously, we're very pleased to complete the day without any major difficulties to the car after such a troubled start here last week," he added

"The car was feeling very good and it's great to bounce back from our dramas to set the fastest time of the day," said Grosjean. "It's clear we have solved the problem we encountered and now we have to complete a very full test programme this week.

"The feeling in the team is fantastic," he added, "it's like last week's issues never happened. My crew told me that the problems would make us stronger, and this is true. The chassis is stronger, and all the team is stronger. We gathered good data today and we have a few interesting things that we would like to confirm tomorrow which should help us make a good step forwards."

McLaren, which had Jenson Button on duty, is planning on gradually introducing a number of new components during this test however, the focus for the opening two days is primarily pit-stop practice with a full race crew and further race 'prove-outs' including set-up work. The back-end of the test will be spent focusing on analysing and learning about the aerodynamic package for Melbourne.

"Having completed more than 2000km at Barcelona last week, today was always going to be more about quality than quantity," said team manager, David Redding. "We wanted to drill a little deeper into our understanding of the car, and that meant undertaking some bigger set-up changes that wouldn't ordinarily be available to us during a grand prix weekend. We made good progress and we're satisfied with today's results."

It was another productive day for Sauber, Sergio Perez completing 118 laps as the Swiss outfit focussed on evaluating new aero components and mechanical set-up work. In the morning the Mexican was on short runs before switching to longer ones in the afternoon. Over the course of the day he only used the medium and hard tyres.

"I think this was a very good day for me," said Perez. "The car was performing well under varying conditions. We are working in the right direction, and I'm very much looking forward to getting into the car again for my final day of testing on Saturday."