Haas is still giving little away about the future of Romain Grosjean.
It is believed Kevin Magnussen, at least, has done enough to stay with the American team for 2019.
'We must thank Gene Haas'
Boss Gunther Steiner admits Haas has done a better job than McLaren and Renault of creating an environment for the Dane to thrive in.
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"For this we must thank Gene Haas. Gene likes to give people space to act and think, which helps Kevin," he told France's Auto Hebdo.
But Frenchman Grosjean has had a bad 2018 season so far, just as Haas is thinking about its drivers for 2019.
Sergio Perez and others have been linked with Grosjean's seat.
"I don't want to talk about the future. We will study this question after the summer break.
I have a lot of respect for Romain on a human level. Who would have taken the risk of joining us three years ago? He believed in us and our project," Steiner insisted.