Toto Wolff reveals that recent crashes have caused Mercedes to halt its update programme.

Since the summer break, the team has witnessed crashes involving Kimi Antonelli in practice at Monza, and successive shunts involving George Russell at COTA and again in Mexico.

Russell's accidents combined with the ever changing performance of the W15 have further complicated matters, with the German team's drivers using entirely different set-ups last weekend.

"In the cost cap landscape, it is a tricky situation," admits the Austrian. "These three shunts put us on the back foot, and certainly the one that happened (in Mexico) was massive. We had to opt for a completely new chassis and that is a tremendous hit in the cost cap.

"(Consequently), we probably have to dial down on what we put on the car," he reveals. "So we'll be having two upgrade packages in Brazil, two floors, but that's basically it.

"There's nothing else that's going to come," he adds. "We have certain limitation on parts where we need to be creative how we're managing them. And certainly there is an impact on how many development parts we can put on the car, because the answer is zero."

Despite the fears over further potential damage, unlike some, Mercedes allowed its two drivers to fight in Mexico.

"They are so good and so experienced that we allow the racing," says Wolff. "There was not a feeling where I thought it's getting a bit hairy.

"I think we made the call to George at the end, where it was clear that Lewis was the faster car, to maybe tell him that one defence on the straight was a bit of a late move. But I don't have any doubts in the two."

Despite the new floors for Brazil, Wolff admits that if the drivers are unconvinced they are free to go their own ways in terms of set-up and whether they use them.

"I'm always open-minded about what the drivers think," he insists. "If I'm certain that George is going to go for the new, Lewis may want to back-to-back the old floor now in Brazil. We will certainly talk with him and see what his preference is.

"There may be something in the aero update package that causes something that we don't understand because we had two massive crashes in the same corner in Austin. But then we had a crash on the old car too," says the Austrian.

"These cars are so on the knife's edge that it will be an interesting experiment in Brazil, to see whether there is a high-speed instability or a low-speed factor. I don't think we can just extrapolate that one is better than the other."