Changes to Formula 1’s aerodynamic rules ahead of the 2021 season have been equated to “regulatory vandalism” by Mercedes’ technical chief James Allison.

Heading into the new campaign, for which teams carry their 2020 cars forward, new restrictions were placed on the floor and diffuser.

That has seen the area in front of the rear wheels, behind the bargeboard, and to the strakes in the diffuser all trimmed.

It’s an effort to slow cars down after they began to reach the limits of circuit design, and tyre safety last year.

“In the previous season, in 2020, we saw that the cars were starting to get a little bit too fast for the tracks and a little bit too fast for the tyres,” Allison explained.

“So, it was important just to bring the performance back a little bit.

“On the back of the car, on the floor, the rules were changed quite a lot.

“It doesn’t look like much when you see the changes in geometry terms – look at the car, it won’t look so different – but, actually, from an aerodynamicist’s point of view, the changes at the back of the car, in front of the rear wheels, in the diffuser behind, in the forward part of the floor, those changes are actually very, very big.

“From an aerodynamicist point of view, they sort of represent a sort of regulatory vandalism that actually knocked the performance of the car right back, about a year and a half, to somewhere around 2019 levels.”

While regulations have placed new limitations on what teams can do, designers have been looking at alternate means of creating downforce.

“Of course, we don’t want to leave the performance at 2019 levels, the regulators didn’t expect them to stay at 2019 levels, they expected us to do our job,” Allison said.

“We’ve had a very exciting time in the wind tunnel doing just that, finding new ways to make sure that, even with the floor chopped and hacked by regulations, we’re able to put a car down on track that has high performance.”

Mercedes ended pre-season testing in Bahrain with the least running of all 10 Formula 1 teams.

That was the result of a gearbox problem for Valtteri Bottas on the opening morning, with the car otherwise running without issue.

It heads into the coming season as favourites for the title, though testing suggested a renewed challenge from Red Bull.

The 2021 Formula 1 season gets underway with the Bahrain Grand Prix next weekend, March 26-28.