Brendon Hartley has said that he will concentrate exclusively on Formula 1 this year.
As he rebuilt his career following his departure from the Red Bull programme some years ago, the now 28-year-old was active across several motor racing disciplines.
In 2018, Hartley will even maintain his ties to Porsche, with whom he won last year's world endurance championship, but he told the NZ Herald newspaper that he will now focus exclusively on F1 and Toro Rosso.
"I will still have an association with Porsche but I won't be doing any races other than formula one, which I think is the sensible thing for me to do because I need to be fully focused," he said.
"I am going to spend all my energy and time on being fit enough, going into the races fresh, sharp and putting every effort into making this season work.
"It is a massive opportunity that I have got there."
It will be a major change for Hartley, who busily juggled his WEC and F1 duties late last year and has accepted with relish any racing opportunity.
"In previous years I have tried to compete in every single race I could," he admitted.
"But I have a big challenge ahead. I am very aware of that."
The 2018 F1 season gets underway with the Australian Grand Prix on March 25.