Pirelli has reacted to the widespread criticism of its 2021 tyres, insisting that the drivers knew what they were getting.

Now fully recovered having previously tested positive for COVID, Pirelli's Mario Isola was feeling the heat again on Friday when the drivers were largely critical of the 2021 tyres they had been given to test over the course of the two sessions.

Leading the assault on the Italian manufacturer was seven-time world champion, Lewis Hamilton, a popular choice with punters opting to take advantage of all current Betway sign up offers, who accused Pirelli of not listening to the drivers and continually getting it wrong.

"We've had the same tyre for the last two years," said the Mercedes driver. "At the end of 2019 they brought a new tyre, which they normally do, and it was quite a bit worse. So then they just said, 'Okay, well now we just keep the tyre that we had from last year'.

"So they've had two years now to develop a better tyre... and we've arrived with a tyre that's three kilos heavier, and it's like a second worse per lap.

"I know for the fans that doesn't really make any difference," he continued, "but from a driver point of view, we're working with brands and partners who are at the forefront of technology, and elevating and moving forwards. And if you're going back after two years of development, I mean, I don't know what's happening.

"It definitely doesn't feel good out there," he admitted, "and it's a worry. I prefer to just stay on these tyres. If that's all they've got, and that's the best they can do, which it clearly is, we'd be better just to stay with this tyre."

"Considering that we are not going to change the compounds, and obviously you cannot have a product that is a revolution if you don't change the compounds, we decided, agreed and targeted a higher level of integrity for the 2021 tyres," said Isola in reaction to the criticism, "and therefore we have worked mainly on the construction.

"I can understand the criticism," he continued, "because consider that they are running cars that are optimised on the current tyre, since two years now. They are the same tyres we used in 2019. So they have a level of confidence, of preparation, they are able to set up the current tyre that obviously is at the end of the life cycle.

"Every time you propose a new tyre, there are some criticisms," he admitted, "there is a change in balance... I heard a comment, I believe it was team radio from Verstappen, saying that he was feeling some understeer...

"We warned the teams that with the new construction, they could have more understeer. We invited the teams to correct the set ups in order to re-balance the car."

Despite the criticism, Isola doesn't believe the 2019 compounds will be retained for a third season and that the teams will get on top of the various issues over the course of next season.

"This is obviously something they will do next year," he said, "I'm sure they will find the way to balance the car and extract performance from the 2021 tyres.

"But they have been focused today mainly on collecting data rather than extracting the performance from the tyre. The driver feels the performance, not other elements. This morning was important for the teams to collect aero data, because the front profile is different.

"We decided not to change the rear profile to avoid changes in the design to the floor. But the front profile is different and for sure needs some adaptation, they have to adapt the car a little bit to the new product."

Check out our Saturday gallery from Bahrain, here.