Haas boss Guenther Steiner says that the US outfit will call the shots when it comes to deciding its 2018 driver line-up despite its all-important links with Ferrari.
Antonio Giovinazzi, the Scuderia's reserve driver, was entrusted with Haas' development with Pirelli this week, a sign that Ferrari's influence with its partner is growing.
Steiner admitted it was early days still with regard to a decision to eventually change its current line-up of Romain Grosjean and Kevin Magnussen.
But when the time comes, the team's opinion will take precedence.
"We are waiting a few more races, but we have control of our drivers."
Haas has an option on Grosjean's services for next season while Magnussen is locked in with a firm deal for 2018.
"Without our current drivers, we could not have done what we have done this year," Steiner told Ekstra Bladet newspaper.
"Romain is sometimes criticised for how he gives his feedback to the team, but we are ok with it because it helps us grow as a team. As long as it does not become personal.
"On top of that, we now have Kevin, and so far he has taken a good step forward. The team is more mature, and the drivers had much to do with that," he added.