The Spaniard completed 172 laps over the first two days of practice at Indianapolis Motor Speedway, on top of the 110 laps run during his test on May 3.

But despite being happy with his progress so far and his gradual acclimatizing thanks to laps run in traffic during Tuesday practice, Alonso admitted he still has more gains to make.

“I feel happy, but definitely not comfortable,” he commented. “Yesterday, especially thanks to the traffic running, I was much more comfortable and happier with the position we are now. [But there is] still a lot to come.

“Obviously in the first couple of days in the car, all the setup changes I did were transparent for me because I was not able to feel the car. Now I start to do so, so I’m happy.

“There’s plenty of time, plenty of running. I’m not ready yet, but I think I will be for qualifying and the race.”

Alonso says driving an IndyCar on an oval requires a dramatically different style to what he has learned during his career. But he is getting used to what he described as a strange feeling.

“The cars, definitely they are different to drive,” he commented. “If you develop your whole career in Formula 1 in Europe, you come here to oval racing and the car felt not natural to drive because the car turns left by itself. So that’s a little bit strange when you approach Turn 1 on the first lap.

“But I had good preparation on the simulator, a lot of information from the team in the last couple of weeks, so I arrived prepared for the feeling.”

Alonso added that he is surprised that the early days of the two-week Indianapolis 500 build-up have not included more off-track commitments, and also was impressed by the fan access. Alonso posed for photos and signed autographs in the pits just before heading out for the first time yesterday.

“Maybe it’s too early to say, but I expected more activities off the track,” he remarked. “Probably I will think differently when I arrive next Sunday, but right now it’s still more or less OK.

“The biggest surprise is to see the fans outside of the garage or even on the pitlane, that’s a completely new thing for me.”