Barcelona day one - Rosberg and Mercedes lead the way 19 Feb 2013
Nico Rosberg sent Mercedes to the top of the timesheets as pre-season testing resumed at the Circuit de Catalunya in Barcelona, Spain on Tuesday.
The German, who along with Mercedes endured an up-and-down first test of the season in Jerez, set his quickest lap late in the afternoon using Pirelli's medium-compound tyres.
We had a mixed day today with some laps lost this morning, said Rosberg, referring to a gearbox problem which temporarily halted his running. However we were able to work through a good programme this afternoon and, of course, it's always nice to be quickest at the end of the day.
In general, I feel happy and comfortable in the car and it feels better than the last time we were here at this track. There is still some work to be done on tyre degradation and our programme this afternoon was helpful in understanding that.
Marginally behind Rosberg was Lotus's Kimi Raikkonen, despite the Finn setting the fewest laps of anyone because of data-logging issues. Like Rosberg, Raikkonen's best time came in the final hour of running when his E21 was fitted with the medium tyres.
It wasnt an ideal day in terms of the number of laps we completed, but the car feels strong and weve made some good progress," said Raikkonen.
"After Jerez its nice to be at a circuit where we race and the E21 is definitely a step in the right direction. Theres lots of work yet to do this week but Im happy with where we are at the moment.
The third-quickest time on the opening day was set by Fernando Alonso in the Ferrari F138. The Spaniard marked his first test appearance of the year by recording the most laps of anyone - 110 in total.
Reigning world champion Sebastian Vettel set the fourth-fastest time of the day as Red Bull continued the development of their new RB9 machine. The German was fastest of all at the lunch break, but was overhauled in the afternoon, despite improving his time using the medium-compound tyre.
Pastor Maldonado clocked the fifth-fastest time for Williams on the day when the team launched their new Renault-powered FW35. The Venezuelan driver, who briefly topped the timesheets in the morning, completed 86 laps - the second-highest number of the day.
"It was a good day today, said Maldonado. "I felt happy after the first run this morning and we then completed a busy day of testing.
"It was great to get out on track in the new car. The FW35 feels like we have made a real step forward. There is still a lot to discover with the new car, but this is a good starting point for us for the season."
Williams technical director Mike Coughlan was similarly pleased with the new cars progress: Pastor was very comfortable in the car which was shown by his early lap times. We had a small water leak this afternoon on a development part, but we were able to fix it quickly to complete our tyre programme.
"We feel confident in the core reliability of the FW35 and look forward to continuing with Valtteri (Bottas) tomorrow.
Toro Rosso's Daniel Ricciardo shaded McLaren's Sergio Perez for the sixth-quickest time of the day, with Paul di Resta eighth fastest for Force India.
Esteban Gutierrez, who brought out the days first red flag with a run-to-dry fuel run, was ninth fastest in the new Sauber C32 and admitted to some struggles.
"It was quite a tricky day with the tyres," he said. "We were struggling with tyre management and, as a result, degradation. We tried different things in the morning, but then in the afternoon we had some issues with the set-up of the car.
"The good thing is we have a lot of data to analyse. This will be the basis for us to understand everything."
Marussia's Max Chilton and Caterham's Charles Pic were tenth and 11th respectively as the first of the four days of testing came to an end.
Testing continues at Barcelona on Wednesday.
Unofficial Tuesday test times from Barcelona:
1. Nico Rosberg, Mercedes, 1:22.616, 54 laps
2. Kimi Raikkonen, Lotus, 1:22.623, 44 laps
3. Fernando Alonso, Ferrari, 1:22.952, 110 laps
4. Sebastian Vettel, Red Bull, 1:22.965, 66 laps
5. Pastor Maldonado, Williams, 1:23.733, 86 laps
6. Daniel Ricciardo, Toro Rosso, 1:23.884, 73 laps
7. Sergio Perez, McLaren, 1:24.124, 77 laps
8. Paul di Resta, Force India, 1:24.144, 82 laps
9. Esteban Gutierrez, Sauber, 1:25.124, 68 laps
10. Max Chilton, Marussia, 1:26.747, 65 laps
11. Charles Pic, Caterham, 1:27.534, 49 laps
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