Mercedes F1 boss Toto Wolff qualified the reigning world champion's new car as "a small diva" that was "a bit toxic to drive" in pre-season testing in Bahrain.
Just days ahead of the start of the 2021 season, speculation is in full force about whether Mercedes' low-key display in testing a troubling sign was or but a temporary setback in the Brackley squad's preparations.
While reliability issues left Mercedes short on mileage in testing, both Lewis Hamilton and Valtteri Bottas underscored the W12's rather unstable handling, at least in Sakhir's windy environment.
Last week, Mercedes chief strategist James Vowles said the team had "a long journey ahead" to figure out and solve the issues impacting its car, but many believe the German outfit is simply playing its cards close to its chest, as has often been the case in the past.
But Wolff denied his crews were sandbagging in pre-season testing, highlighting instead the W12's temperamental characteristics.
"We've had some great performances over the years and that is why everyone is saying that we are sandbagging," Wolff told Austrian broadcaster ORF.
"I think that we were the team that was running with the most fuel, but regardless the car was a bit toxic to drive and fairly unstable, especially with the crosswind.
"It seems like we have a small diva, like the car from two years ago, that we haven't really understood yet."
Wolff admitted however that this year's limited pre-season testing period which was reduced to just three days did little to help its efforts.
"The fact that we only had a few days of testing certainly didn't help," he said. "We haven't yet understood the car the way we want to.
"We have some small issues that we have to resolve, so we certainly aren't as prepared as previous years."
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