As he has not completed six races with it, he will inevitably be penalised.

The FIA also revealed that the team has known about the issue since Tuesday morning.

The team found the gearbox had been damaged after Baku and it has decided to replace it as a precaution.

A note from the FIA's Jo Bauer said: "The above driver did finish the last race in Baku and this gearbox change was before the six consecutive Events expired.

"As this is not in compliance with Article 23.5a of the 2017 Formula One Sporting Regulations, I am referring this matter to the stewards for their consideration. The team informed the technical delegate about the gearbox change on Tuesday, 04th July 2017, at 11:29 hours."

Hamilton had topped both of Friday's practice sessions.