Mercedes: 'Not sure yet that Hamilton will get fourth engine'

Max Verstappen will take his fourth Honda engine of 2021 in Russia and that means a grid penalty for the Dutch driver. Helmut Marko expects title rival Lewis Hamilton to have a fourth power unit fitted in Turkey, Mexico or the United States, but if Toto Wolff is to be believed an engine change for Hamilton is not a certainty just yet anyway.

"All the teams are having a hard time getting through the season in terms of engines," Wolff told Speedweek.com. "It's not just about durability, but also the extent to which an engine loses power over the course of its life. A dropout while your rival is winning means you need at least four good races to make up for that."

For Hamilton, it's going to be tight to finish the season with three engines in his pool. A DNF could be catastrophic for the seven-time world champion's title chances. Still, Mercedes hasn't decided whether or not to use a new engine.

Wolff and Mercedes wait and see

"We are keeping a close eye on how the engines are performing in terms of stability, at the moment we don't see any difficulties. But we are looking at it from weekend to weekend. We don't want to rush things. It can also happen that you get involved in an incident during a weekend and have to start from the back anyway. That would then be the ideal moment to replace the engine," said the Austrian team boss.