George Russell expects Williams’ form to “yo-yo” this season due to a peaky aero concept on its 2021 Formula 1 car.

Williams’ aerodynamic philosophy for its FW43B will be exposed to the wind, with the British squad believing that will result in dramatic performance swings across the course of the upcoming 23-round season.

Russell, who set the sixth-best time on the final day of pre-season testing, revealed that conditions in Bahrain had “brought out the worst” in its 2021 car and confirmed what the team had predicted.

“This test has been a very productive one for the team with an incredible amount of laps, no issues reliability-wise,” Russell said.

“But we knew ahead of the season and it was confirmed over these three days that our car was incredibly sensitive to the wind.

“The conditions of these past three days have probably brought out the worst of the car, which has been positive, in some ways, to analyse.

“But equally, I think you will see that our performance will yo-yo this season and unfortunately quite often at the hands of the wind.”

The 23-year-old Briton explained that the aero route Williams has taken comes with the caveat of knowing the team’s performance will ultimately be out of its control due to having a less consistent car.

“The positives are that when the wind is in a favourable direction, the car is very fast,” he added.

“We talk about this yaw sensitivity, so the yaw angles get very high at low speed, especially when there’s a bit of wind, and that’s where our car is very poor.

“So the positive is there is a fast race car in there. But unfortunately, it’s almost out of our hands when we can excel. Had the wind been neutral for this test, our lap times would have been much faster.”

But Russell indicated the approach was deliberate in Williams’ bid to maximise the potential of its car on days when everything goes well and subsequently capitalise by scoring points.

"We've opted to go down a bit of a route to give more downforce at the expense of being a bit more sensitive," he said.

"Ultimately, we recognised that we only need a couple of [good outings], and if we were consistently at a set pace, as we probably were last year, we consistently won't be scoring points.

"You've only got to be quick at two races, for example, and you will finish potentially eighth or ninth in the constructors' championship. Haas scored three points last year and Alfa scored eight. We want to try to be as quick as possible when the stars almost align.”