James Vowles was more concerned about Williams' limited running ahead of the weekend than Alex Albon's FP2 issues, stressing the need for track time.
A cold street circuit that has only been used once in the past causes enough problems as it is but Williams' task has been made a lot harder given their limited running.
A fuel system issue prevented Alex Albon from beginning FP2 on time but even when he did get out, his time on track did not last long with the 28-year-old forced to park his stricken car on the side of the road.
The mechanical issue comes after a number of crashes put Williams under pressure to get both cars ready in time for the final triple-header but there is clearly still more work to do before FP3 and quali on Friday.
Asked on Sky F1 if he was concerned that this could be an ongoing problem for the team, Vowles said his "bigger worry" was not getting enough track time.
"It's contained," Vowles said of Albon's issue. "My bigger worry is that you need every lap really around here.
"You can see the drivers getting up to speed, and when you're limited in the amount of learning you have, especially with just one car, Franco (Colapinto) still getting up to speed on the circuit, it puts you on the back foot. That's my biggest concern."
Asked how motivated the team had been to prepare both cars in time for Las Vegas, Vowles said that the "fighting spirit" seen during Williams' title-winning days is still present today.
"I'd say that's built into Williams," the team principal, who was appointed in 2023 said. "And that's just that's the heritage that comes with a team that's won nine World Championships.
"That's still got that fighting spirit underneath it and I think more than any other time, we can see the pathway that we're pulling ourselves out of where we were and going towards where we are at the moment."
Alpine's surprise double podium in Sao Paulo has practically confined Williams to P9 with Sauber 17 points behind but P8 VCARB 27 points ahead.
