Presenting at an event with the Mercedes title sponsor Petronas in Italy, Valtteri Bottas confirmed there is an imbalance with the new W10, making the car a bit of a handful to drive in some corners.

“We were struggling a bit over the week to find a good balance for all the corners. There were some corners that were good, some corners we would have balance issues and other corners we would have massive balance issues”, said Bottas.

The Finnish driver added that the performance improved significantly from the beginning of the testing sessions. However, he remarked how new updates are needed to fix the current issues.

“We’ve been improving massively in the first three days… [and] it’s nothing fundamentally wrong, I feel. I think there is a lot of potential, but it’s not yet quite there”.

“It seems like, balance-wise, it’s a little bit on the knife-edge at the moment”. 

“We do need to make improvements”.

“We were getting to a much better state at the end of the week, but some of the handling issues can only be sorted with some upgrades. We’re hoping to fix those hopefully soon.” 

Bottas confirmed the impression that Ferrari is currently leading the grid, underlining how the  team is motivated to figure out the problems and get back to the head of the grid.

“ I feel a sense in the team of a bit of an excitement to discover more about the car and to improve it – because at this point, it looks like we are not miles ahead of everyone. It seems like… Ferrari are in a better place. So I think it motivates us, but obviously we would love to be ahead in Melbourne.”

Similarly, Lewis Hamilton told that Mercedes is behind Ferrari, pointing out how the new car has to be improved.

“At the moment we are behind,” he said.

“So, we don’t approach the first race currently at all relaxed, not that we ever do. We still have a lot of work to do.

Mercedes boss Toto Wolff agreed, recognizing Ferrari as the most competitive team over the first pre-season tests, adding, however, that the competitive performance cannot be judged before Melbourne, as all the teams are intensely developing their cars.

"In Barcelona [test] one  what we have seen is that Ferrari is ahead of the pack," he said. "The car looks fast and is fast on lap times.

"They could probably have gone 1.5 seconds faster if they wanted to, and that is the fastest car we have seen in testing so far.

"Then it is pretty much everybody bunched up, which is pretty exciting between all the other teams.

"Now it is about seeing what happens in Barcelona [test] two.

"I have a feeling everybody will bring stuff to the car and then again in Melbourne. So probably only then will you be able to judge the competitive balance and not before."

Read More about winter tests: Antonio Giovinazzi and the Alfa Romeo C38 two of the biggest surprises from barcelona's test