Both Mercedes drivers are set to receive new gearboxes ahead of the Formula 1 Bahrain Grand Prix, with Lewis Hamilton set to pick up a penalty as a result.
Damage was found inside Hamilton's gearbox as the team prepared his car in Bahrain, leaving it no choice but to make the change.
It means the 2017 world champion will receive a five-place grid penalty following qualifying, which will see him start sixth at best.
The penalty comes because the current gearbox had not been used in six consecutive events.
Across the garage, Mercedes has also opted to change the gearbox in Valtteri Bottas' car, though as the Finn will not pick up a penalty.
It will make his second new gearbox of the year, having had one replaced following his qualifying crash in Melbourne two weeks ago.
The nuance within the rules allows teams to replace a gearbox without penalty after replacing a damaged unit at the previous event.
Hamilton ended the opening day's running in Bahrain fourth fastest, one spot behind Bottas.