The Finn set the fastest time on day two of the second group session in Barcelona, clocking 108 laps for a best attempt of 1:23.261 on the supersoft tyre. This came after Bottas already posted the second quickest mark on Tuesday. But while buoyed by his team’s progress, the 26-year-old refuses to get carried away.
“I feel we are more complete at this point even though there have been less days before Melbourne,” Bottas said. “I want to keep my feet on the ground as we haven’t done a single race yet but I am positive with what we have done over the winter and in testing.
“I feel there is quite a bit more to come. We have been learning a lot in the four days I have been driving and the days with Felipe [Massa]. There are still two days left and we have more to come. We also have some bits for Melbourne and if they work it should be a step. It is a good starting point.”
This was Bottas’ final day in the FW38 before the season-opening Australian Grand Prix. The Finn had to miss last year’s event when he suffered a lower back injury in qualifying.
Massa will conclude Williams’ 2016 pre-season testing programme, with the Brazilian scheduled to run on Thursday and Friday in Barcelona.