Mercedes: Tough out there with the low temperatures 21 February, 2013 Nico Rosberg Nico Rosberg completed his fourth day of pre-season testing this afternoon at Barcelona’s Circuit de Catalunya, running a total of 108 laps in cold but dry conditions. His pre-season mileage now stands at 1471 km. The morning programme focused on data gathering and set-up adjustments This afternoon, Nico concentrated on longer runs with the hard and medium tyres Nico ran soft, medium and hard compound tyres during the day’s programme His fastest lap of 1:22.611 was completed on the medium tyre on lap one of a seven-lap run Lewis Hamilton will complete the fourth and final day of this week’s test programme tomorrow. Nico Rosberg: We didn’t have a perfect morning and it was tough out there with the low temperatures. They were causing a lot of tyre graining, which made it difficult to do much useful testing. It was a few degrees warmer after the break and that gave a completely different picture. In general, I’m pleased with what we’ve achieved this week – I did a lot of mileage and the team has done a good job over the winter. I feel more comfortable in the car and the balance is quite good, but we still need to work in a number of areas. That’s why I’m looking forward to testing next week and to see what progress we can make. Content on GrandPrix247.com by: staff & contributors, Reuters syndication, GMM service, Getty Images, Formula 1 teams, sponsors & organisations.