Williams' Valtteri Bottas concluded his two days of testing fully satisfied with the outcome of his program which focused on development rather than outright performance.
"Everyone in the garage has been working very hard," Bottas said.
"I am pleased with the amount of laps we did, with the mileage and reliability that we already have in the car.
"The car is already feeling better than last year's car but I'm sure thats' pretty much the case with all the team here. Because we were just going through our program and not focusing on the performance yet, there is still a question mark as to where we are compared to the other teams.
It's no secret that Bottas is seeking his first Formula 1 win this season, and that anything short of that realisation would prove a big disappointment this year.
"I'm really looking forward to that first win that's for sure. I'm also looking forward to really getting on top of the problems we had last year compared to the main teams.
"I think we've already addressed some of the issues, but we really need to master the tyres as there were a lot of races in the last two years where we really struggled on that front."
Bottas will hand over driving duties to team mate Felipe Massa today, but the Finn is already looking forward to next week's second test.
"I think it will be interesting to follow what things Felipe is going to try with the car. I'm looking forward to next week now as well, to get back in the car and try to get a bit more out of it."
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Who is driving when during the first pre-season test
GALLERY: Pre-season testing day two
