Haas are currently leaving the door open for a driver change in 2017.
The American team has immediate problems to solve, given a spate of recent brake failures, the most recent being Esteban Gutierrez's in Austin.
Asked why it is happening so often, team boss Gunther Steiner told Auto Motor und Sport: "You would need to ask [supplier] Brembo."
Amid that problem, the new American team are in the middle of negotiations for their second seat, with Romain Grosjean almost certainly staying for 2017.
As for Mexican Gutierrez's place, Steiner admitted: "We don't know.
"It is frankly still completely open. We will not make any more deadlines and given no timelines, because if you don't comply then you are no longer taken seriously," he added.
This weekend is Gutierrez's home race and so it is an awkward time for the 25-year-old to have his future so unclear, but is quoted by Marca as saying: "Things are going well. We have some options."
Haas have picked up 29 points so far in their debut championship.
