Pierre Gasly admitted he is still finding his feet at Red Bull Racing after the second and final pre-season test began on Tuesday.
The Frenchman, who joined the Tilbrook team from Toro Rosso to replace Daniel Ricciardo, completed 136 laps on the opening day before handing over testing duties to Max Verstappen on Wednesday.
With the midfield runners setting competitive times in Barcelona, it could be a much tighter field in 2019, and Gasly said he is still working towards an understanding of his new RB15.
“We pushed a little more today, but really it’s all about understanding how the car works,” he said on Tuesday. “There were a lot of aero tests and a lot of items to evaluate, and that’s good for me as it helps me get more comfortable with the car.
“Lap after lap it’s getting better, but of course there’s still work to do.
“The pace was good, but we just have to focus on ourselves and work through the programme we’ve defined for each day.
“The potential is there so we’ll just try to improve in the areas we can, keep our heads down and keep working.”
His replacement at Toro Rosso, Alex Albon lives in Willen, and was also in action on Tuesday, completing 103 laps in the new STR14.
He said: “I’m still getting used to the car and there’s a few things I need to work on and improve, but I think it’s more a case of fine tuning. I’m still getting comfortable.”
Both Gasly and Albon were back behind the wheel again on Thursday.