Friday's pacesetter Valtteri Bottas enjoyed a good start to his US GP weekend, but the Finn is facing a minimum five-spot grid drop in Austin – his third grid penalty in four races – following another engine change in the Mercedes camp.
The German manufacturer is adding new units left and right to mitigate reliability issues, with Bottas taking on a sixth ICE element at the US Grand Prix, while Aston Martin's Sebastian Vettel and Williams' George Russell were also handed fresh Mercedes hardware at the Circuit of the Americas.
The changes don't bode well for Lewis Hamilton whose odds of suffering another grid drop before the end of the season appear to be increasing.
Contrary to Sochi, where Bottas was the recipient of a complete new power unit, Mercedes has added only an Internal Combustion Engine to the Finn's engine inventory.
In Turkey, Mercedes team boss Toto Wolff opened up about the Brackley team's PU troubles, revealing that replacements were undertaken to "contain the problem" and to avoid a costly DNF with regard to Hamilton.
According to the FIA's latest communication, both Vettel and Russell have received fresh Turbochargers and MGU-H elements, which entails back of the grid starts on Sunday for both drivers.
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