Mercedes has a long history of winter tests in which the team is far from going all out, only to declare that it is lagging behind its direct competitors. This year, too, Mercedes did not finish on top. Yet now there is a difference.
Problem
No doubt Mercedes will play a significant role in the first race next week. But top favorite, the team does not seem to be one. Especially the porpoising seems to be a problem, as 
Lewis Hamilton and 
George Russell also experienced during the last day of testing. In the end, Mercedes finished one second behind 
Max Verstappen, who ended the week as fastest on behalf of Red Bull. 
 Afterward, Russell indicated at 
Motorsportweek.com that the porpoising is anything but comfortable, but that he didn't care if the performance was there. But the Briton had to admit that currently there is not. According to Russell, Mercedes seems to be a step behind Red Bull and 
Ferrari, so there is still a lot of work to be done in the coming week.
Not exceptional
Although Red Bull and 
Ferrari had a nice gap to Mercedes, Russell is still not hugely impressed with these teams. In his view, the competition is not exceptional, adding that Mercedes is not as competitive as it would have liked to be. The problem? The bouncing of the car, which prevents the car from getting into the right flow. According to Russell, they are working hard internally to solve this problem.