Felipe Nasr will not be able to end his early 2016 troubles by switching to a new Sauber chassis this weekend in Russia.

After complaining about the handling of his chassis in all three race weekends so far and suspecting a flaw, it had been reported that Nasr would get an all-new version of the C35 for Russia.

"I am 100% sure the car is not right," Nasr was quoted as saying by Brazil's UOL after the Chinese Grand Prix.

"I'm struggling all the time but [teammate Marcus Ericsson]'s happy with the car from the start. I drove that car in Barcelona and I was happy too," he added.

However, spokesman Robert Hopoltseder told Brazil's Globo that while the Swiss team is working on a third chassis at present, they are not sure it will be completed in time for Nasr to use it at Sochi.

Amid the team's financial troubles and Nasr's predicament, teammate Ericsson said after the Chinese Grand Prix that he is willing to swap chassis with Nasr in Russia.

"Why not? I'm willing," said the Swede. "I wouldn't mind. I will make this proposal and see what he says."

Ericsson suspects that he is simply out-performing Nasr on merit.

"I was already stronger at the end of last year," he said. "I have worked very hard in the preseason to be even stronger this year and I have confidence in the team and the car."

Neither driver has accrued any points in 2016.