Guenther Steiner fears the pressure got to Esteban Gutierrez at Monza as he fell from tenth on the grid to 20th as the Italian Grand Prix got underway.
On Saturday, the Mexican driver was Haas' hero as he clinched the first Q3 berth in their debut campaign, qualifying in tenth place.
However, 24 hours later it all came to nought as he failed to make a clean start and fell all the way down to 20th place.
Gutierrez recovered to finish the grand prix in 13th place, two positions behind his team-mate Romain Grosjean.
"It was a driver problem, missing the start," said Steiner. "I guess the pressure got to him.
"It's a missed opportunity for us but also for him.
"These positions, they are hard to get as the field is quite set now."
And with Gutierrez's future still undecided, the Haas team boss concedes that Sunday's mistake did not come at the best time.
— Haas F1 Team (@HaasF1Team) September 4, 2016
"It's not the perfect timing but I don't think we put that kind of pressure on him," he said.
"It's not like 'if you do this, you get this'. It's a negotiation point."
As for Gutierrez, he says he did his best to recover but admits he had lost too much ground at the start.
"It was a very disappointing start to the race losing a lot of positions," he said.
"It was very tough to recover, but I did my best.
"I struggled in the first stint with the overall pace, starting with the scrubbed tyres from qualifying and fighting with people which were on new tyres.
"It wasn’t very easy, but we kept ourselves together and pushed really hard to recover everything we could, but what we lost in the beginning was too much to get back to where we started."
The 25-year-old remains point-less for this season.
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