Sergio Perez was quickest in Barcelona on Wednesday, but he also admitted that Jenson Button still rules the McLaren roost.
Asked by Spain’s AS newspaper to rate his adaptation from Sauber to McLaren, the young Mexican answered: "From zero to ten, I would say it is a 6 or a 7."
Perez said the "management style and philosophy" of Woking based McLaren and the Swiss team Sauber is fundamentally different, adding that his experienced teammate Button has the advantage of having being involved in the development of the new MP4-28 car.
"Jenson is obviously a very experienced driver and has put a lot into the car," he said.
"It is slightly adapted to his style, so it’s up to me to adapt to that, but I’m sure I will be completely ready in Australia.
"In any case, I am delighted with McLaren. All my life I’ve dreamed of being on this team, and from day one I have felt at home."
Perez, 23, played down the prospect that his relationship with McLaren could break down, just as it did with other Latin drivers like Juan Pablo Montoya and Fernando Alonso.
"Every year, every race, there are different circumstances with the different drivers," he said. "There have been other Latin drivers who have won championships here.
"Nationality means very little. The most important thing is that you have the right circumstances and a good car.
"The car is very different from what I was used to, but it is competitive," he added.