Toto Wolff is not ready to write off Ferrari's chances of winning the 2020 world championship.

In testing, the Maranello team's new car was conspicuously off the pace, having improved in the corners but become significantly slower in a straight line.

The obvious conclusion is that the wrangling over the legality of Ferrari's 2019 engine had resulted in a serious performance drop for 2020.

But Mercedes boss Toto Wolff is not so sure.

"Let's wait and see if they are really slower. They were bluffing in the tests," he told Osterreich newspaper.

Ferrari boss Mattia Binotto insists that the car's problems are real, but former F1 driver Christian Danner told RTL: "There is definitely a big question mark about Ferrari after the tests.

"You could see their progress in cornering, and that the car wasn't fast enough could have been the chassis or the engine.

"They seem to have problems with driving at maximum power," Danner added. "They built a completely new engine over the winter, but for whatever reason they are still too slow."

It is impossible not to link Ferrari's struggles with the scandal surrounding the secret deal reached between the team and the FIA over the 2019 engine.

In a letter of response to the seven non-Ferrari affiliated teams, FIA president Jean Todt lashed out at what he calls "injurious and defamatory" charges.

But Danner thinks the angry teams are justified.

"The teams understandably want to know how the engine rules and the possible gray areas affect their own performance," he said. "It's obviously about money as well."