According to Mercedes-AMG boss Tito Wolff, number two driver Valtteri Bottas is struggling in the new W08 configuration.
The veteran Finn has struggled with the car since the summer break and has said that his woes in the Mercedes stems from a lack of confidence.
In Sepang, the Mercedes team boss told journalists that whatever the problems Bottas faces with the WO8 configuration, they still have faith in the Finn’s driving abilities.
"Yes, I'm worried because I want Valtteri to do well. Everyone wants Valtteri to do well.
"Valtteri seems to struggle more in having the car in the sweetspot than Lewis,” Wolff said.
"There are so many factors that play a role, but I have no doubt his intelligence will put the jigsaw together.
"We have many more races to do it together and undo the problem.
"Very good drivers are able to dig themselves out of a difficult situation and I have no doubt he will do that.
"Somebody clever said, 'smooth seas don't make tough sailors', and if he can dig himself out of his current underperformance, then he is going to come out much stronger.
"We have seen very good performances from him this year and he had a dip in form in the last races. But nobody is doubting Valtteri."
That must be good to hear for Bottas.
However, the issues surrounding the WO8 set up has been a constant presence all season according to Wolff, who said that the different driving styles used by Brit Lewis Hamilton and Bottas may be a contributing factor.
"We have a capricious car,” the German race director said.
"It has a very narrow operating window with the tyres, where the tyres generate optimum grip.
"And dipping in and out of the window is the fundamental story of 2017 for us.
"Driving style plays a role. Lewis was able to better adapt to the problem than Valtteri.
"But changing driving style is not something that comes easy to anybody."
Hopefully Bottas rediscovers the form he had before the summer break.