Red Bull would have protested Mercedes' DAS in Australia

With Mercedes having caused a stir at pre-season testing when it unleashed the concept that alters the toe angle of the front wheels through drivers pushing and pulling the steering wheel, rivals had been pondering whether or not they accepted the device was legal.

But while some outfits conceded that Mercedes had cleverly exploited the regulations, sources have said that Red Bull remained convinced that DAS was not legal.

And their stance was such that had Mercedes run the device in a practice session, then it would have lodged a protest.

It is unclear on what specific rule Red Bull would have challenged the DAS design, as Mercedes had already been told by the FIA that in the governing body's opinion, the system complied with the regulations.

However, the ultimate legality of a car can only be properly verified by race stewards at a grand prix – something which would have been found out had the Australian Grand Prix got as far as running.

Mercedes driver Valtteri Bottas had said before the event that the team was set to run DAS, and would have to weigh up the potential threat of it being protested.

"We would be happy to run it, but it is up to the team to calculate the possible risk of it being taken away," he said.

"In short answer, yes, we would like to keep it. But if there's a big risk we don't, there is no big problem then."