Marcus Ericsson said his first IndyCar test took him back to the “passion of racing” ahead of his switch from Formula 1, which he described as “a bit artificial”.

The Swedish driver will contest the IndyCar Series next season with Schmidt Peterson Motorsports after losing his full-time seat with the Sauber F1 team at the end of 2018.

Nine days after competing in the F1 season-ending Abu Dhabi Grand Prix, Ericsson got his first taste of IndyCar machinery as he completed a maiden test outing in SPM’s Honda-powered car at Sebring on Tuesday.

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“This sort of gets me back to why I fell in love with racing,” Ericsson said.

“F1 is always going to be F1, you know? But it’s sort of a bit artificial in some ways.

“You always go to these perfect places, and that’s not racing, I would say. This takes me back to the passion of racing.”

Ericsson, who lost his F1 drive despite enjoying his strongest season to date in 2018, will combine his IndyCar duties with a test and reserve role at Sauber - which has opted to re-sign Kimi Raikkonen alongside rookie Antonio Giovinazzi for 2019.

The 28-year-old believes he can transfer his knowledge gained in F1 across to his new series but admitted driving in IndyCar requires a lot more work.

“As a driver, you have to work this car a lot more,” Ericsson explained. “F1 always starts from perfection, whereas here you have to deal with the car you have and then sort of perfect it.

“It’s a lot more work from the driver. That’s the biggest difference. The car looks really cool. I’ve watched a lot of clips on the internet to prepare myself for this.

“I feel like I definitely have stuff that I can bring from my F1 experience to help us as a team to move forward, but I also think the team is really at a high level.

“I’ve been impressed with the way they work and the preparation they do before a test with all the prep on the setup side. That’s been quite impressive.

SPM general manager Taylor Kiel was left impressed by how quickly Ericsson adapted to his new surroundings and reckons he is already well-prepared for a “steep” learning curve.

“I’m totally impressed with his outlook on this test,” Kiel said.

“It’s difficult for a driver to come into a test and not be focused on the lap times. Just to get in the car, understand it, really take the time to understand the nuances.

“How you come into pit lane, what you do when you’re in pit lane, and what you do when you leave pit lane - all of the things we’re going to ask him to do on track. He’s responded very quickly to that.

“To the layman, this car looks similar to an F1 car, but it’s such a different animal,” he added.

“There’s no power steering, there’s way less downforce and the brakes coupled with the downforce are not as good in an IndyCar.

“There are a lot of things that he needs to get used to and that’s what he’s working on doing. So far, so good.

“The learning curve is going to be steep, but he’s very well-prepared mentally to attack that right now.”

Ericsson is set to for another test with the SPM squad in the new year as preparation for the 2019 season-opening Firestone Grand Prix of St. Petersburg on March 10.