Chip Ganassi Racing's rookie star Felix Rosenqvist says the IndyCar Dallara-Honda is the most difficult car he has needed to master in his career.
Despite not turning 28 until November, Rosenqvist has enjoyed a remarkably varied career since winning the Formula Renault Asia title back in 2007.
His path since then has encompassed Formula Renault, Formula Palmer Audi, Formula 3, Indy Lights, GT championships, DTM, IMSA's Prototype Challenge class, Formula E, Super Formula, Porsche Carrera Cup and LMP2 cars.
But the 2015 European Formula 3 champion says that learning the intricacies of competing in IndyCar has been the biggest demand yet - and required a revised mental approach.
Rosenqvist goes into this weekend's IndyCar season finale at Laguna Seca leading the rookie standings by 26 points over Dale Coyne Racing driver Santino Ferrucci and 49 over Austin race winner Colton Herta of Harding Steinbrenner Racing.
Currently eighth overall in the championship, Rosenqvist said "the rookies have definitely made a statement this year" but admitted his early form might have actually been too good.
"Having raced all over the planet, I would say that IndyCar is the toughest beast yet to master for me," said Rosenqvist.
"I think Colton Herta and I have had similar years where it took off a bit too fast, and then the reality of IndyCar struck us, and a change of approach was needed.
"I have definitely calmed down during the year, trying to take what's there every weekend instead of forcing myself into errors trying to go for the top spot at any cost.
"I also think that's why I'm the leading rookies right now.
"The speed has been there from the start, but it's just so much more needed to take the points every weekend.
"Speed alone will not give you success in this championship."