Sauber's Monisha Kaltenborn says the Swiss outfit will run the whole year with its current spec Ferrari engine, discarding any upgrade prospect.
Sauber is running a year-old power unit supplied by Maranello, a deliberate decision centered around financial constraints and the desire to benefit from a reliable and proven unit.
But the power deficit of the older engine compared to its 2017 version is clear, leading some to suggest that the Hinwill-base outfit could upgrade at some point this year.
Kaltenborn however says that won't happen, but she also believes it's a bit early to judge the unit's relative performance.
"No. That we knew," she said.
"I think it's far too early to say because Australia is definitely not a representative track. We need to wait a couple of races, and then we'll see how big it [the gap] really is," she added.
Kaltenborn conceded that Sauber's entry into the new season hasn't lived up to the team's expectations although progress is in the works.
"We hoped we were a bit better, because we've been following some new concepts," she explained.
"Of course others started earlier, they have understood after the tests where they need to do a few changes. But otherwise I think the basis is there.
"We need to develop that now, and we have a development plan in place. We have bits and pieces coming here, and then we have an intense testing programme in Bahrain.
"We are planning a bigger package in Barcelona and then we'll take it from there."
GALLERY: F1 drivers' wives and girlfriends
Keep up to date with all the F1 news via Facebook and Twitter
The opening day of running at the Las Vegas GP was a smooth but chilly…
Williams is continuing to fight uphill battles this weekend in Las Vegas as a knock-on…
It was a solid start to the Las Vegas weekend for Ferrari with Carlos Sainz…
Lando Norris didn’t hold back in his assessment of McLaren’s performance on the opening day…
Lewis Hamilton was particularly happy with his opening day of running at the Las Vegas…
Red Bull fears that its prospects for this weekend's Las Vegas Grand Prix - which…