The Swiss-based team has been evaluating ways to extend its technical partnership with Ferrari, and one option being looked at was to adopt a Haas-like approach of buying some parts from the Italian manufacturer.

But having weighed up what was best, Sauber team principal Fred Vasseur says complications caused by trying to integrate new parts into its advanced 2018 car design have meant it would not really be a good option for his team.

When asked by Motorsport.com about the latest on the non-listed parts decision, Vasseur said: “It is not an easy step also because we were already in the process to develop the car in the wind tunnel, and to take some parts from another car and add it to an ongoing project, it is not ideal.

“It is not that you take the front axle of the Mercedes and the rear axle of the Red Bull that you will make a good car.

“For the future we can extend the parameters and have a much better approach if we sort the deal earlier in the season.

"But we have to consider that we did the move in the middle of July, it was very late, and I was really on the edge at this stage to think it was too late. We had already to feed the engine into the car, so I am not sure it makes sense.”

While Vasseur thinks buying some non-listed parts could be an option in the longer term, he is mindful of not losing the expertise his own team has at present too.

“I don’t want to lose the know-how, as it is one of the skills of the company, and I don’t want to lose the know-how of how we make the wishbones, or how we have to develop the car.

“We have to take care and find the right balance for this. If you have a short-term view, it is easy to say that it will be much better for Sauber to buy the parts [from Ferrari].

"But from the midterm view or long-term view, if you want to develop your own project and perform, we don’t have to stop to have a good technology in-house.”

He added: “We will see for 2019 how it works and if we can develop, but for sure the collaboration with Ferrari will be a lot better next year, as last year was a bit complicated.

“I am not fully convinced that the future of Sauber is to become a Ferrari B-car. We have to develop our own project.”