Wollf on engine change: 'We're looking at it from weekend to weekend'

Lewis Hamilton's victory on the Sochi circuit at the Russian Grand Prix ensured Mercedes kept its perfect score at that track. Never before has any other team won an F1 race there. Still, Toto Wolff's men won't be entirely comfortable after this victory. Without rain, Lando Norris probably would have won, and after an epic ending Max Verstappen managed to drive from the back to second place.

As a result, Lewis Hamilton's lead over the Dutchman is just two points. With a couple of Red Bull Racing circuits and a possible engine change for the Briton in the offing, the Brackley team are under pressure. In Russia, Bottas was used to make life difficult for Verstappen at the back of the grid with an unnecessary engine change, but to no avail: the Red Bull Racing driver passed the Finn on lap six and was unable to play a tactical role for his team.

Wolff, however, states at F1.com that the engine change for Bottas was not to thwart Verstappen: "I think we did the engine change not only because we wanted to stockpile, but also because we want to understand the performance of the engine, and that has given us some question marks." What question marks would be involved, however, Austrian would not say.

"We'll just take it race weekend by race weekend - and [then we'll] reassess the performance of the power sources and then make decisions. At the moment we are reassessing the performance of the power sources because we have question marks, and therefore we have not yet decided which engines will go back into the pool," Wolff added.