Mercedes boss, Toto Wolff admits that bottoming and 'parachute-like' drag are the main factors compromising the W13's performance.

His words come at a time the team continues to take one step forwards and then two back, often between sessions.

"Our engine guys made a great job in understanding how we can optimise the software and the deployment of the power unit since the beginning of the year," the Austrian told the media in Baku.

"So our problem here is not the engine, we have a car that is that is too draggy, so the drivers made the comment that it seems like we are having a parachute behind the car.

"So we need to, I think, between the draggy car, and the bottoming, this is the main effect that we are seeing here on the straight.

"In Barcelona we had a big rear wing and the car was pretty stable on the straight and we were among the quickest, but there's never one thing and certainly the engine is not the area that I would want to point at that stage.

"Others like Ferrari has it too here," he said of the porpoising, "even a bit worse.

"At different pieces of the track, we are bottoming-out badly, which affects our aerodynamic, and affects our straight-line speed greatly. And as a consequence, the ride is not very good. And this can cost several tenths, and yesterday we were losing a second on all straights to Ferrari and Red Bull."

As drivers, Lewis Hamilton and George Russell continue to express their fears over the pounding they are taking as a result of the porpoising, Wolff fully empathised.

"We are seeing cars that don't have the issue and then others that have it worse," he said. "Clearly I can talk for our two drivers they are having issues.

"It goes to a point that even a physio can't fix it sometimes. So we need to see how that develops and understand also why it's much tougher in some cars than in others."

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