Christian Horner has revealed Red Bull’s focus on its new challenger for the upcoming F1 season has been designed to cure an issue that eventually led to the departure of Sergio Perez.

Perez was released at the end of last season following an abysmal run of form that resulted in Red Bull failing to defend the constructors’ title it had won the previous two years.

Red Bull dominantly started last season, notably with Max Verstappen winning four of the first five grands prix, and being ably supported by Perez.

But Perez’s campaign crumbled in dramatic fashion, with the Mexican driver scoring a wretched 49 points in the final 18 races to leave Red Bull third in the constructors’ standings, 77 points behind new champions McLaren.

Horner has highlighted the fact the RB20 suffered from a particular problem that Perez was unable to drive around, unlike four-time champion Verstappen who could “mask” the concern with his particular driving style.

Those issues have been targeted to ensure this year’s RB21 offers a more consistent drive at a variety of circuits and in whatever conditions.

“We’ve a good understanding of things development wise,” said Horner, speaking to select media, including RacingNews365.

“Around Imola, we introduced an upgrade that made the car far more peaky in its performance, and it had a very narrow operating window.

“When you got it [the car] into that window, for four straight laps in Austria, for example, they were all good enough for pole. It was very much in that window.

“If you stepped a millimetre either side of it, it became much more of a problematic car to drive, which Max was able to mask and drive around. I think that’s what hurt Checo particularly, is that window was so narrow.

“So what the engineers have been very much focused on over the winter is how you broaden that window, not necessarily adding ultimate performance, but just broadening the window so that you’ve got, across the different challenges and circuits that we visit, a much wider operating window.”