Bottas has moved onto his fourth internal combustion engine (ICE) of the season and also taken a fresh turbocharger (TC), MGU-H, MGU-K and new exhaust system (EX) on his Mercedes.

A Mercedes spokesperson confirmed the power unit change was a "strategic" decision. 

As a result, the Finn is set to start the Italian Grand Prix from the very back of the grid.

However, Bottas will be able to start Saturday’s sprint race at Monza from wherever he qualifies on Friday evening as the grid drop will only be applied for the grand prix itself.

Earlier on Friday, Mercedes boss Toto Wolff had indicated that the team was considering taking engine penalties in Italy.

 “I think we are all struggling on power units,” Wolff told Sky Sports.

“Maybe not only reliability but also how these power units work hard and how they’re degrading.

“There are thoughts, definitely, for this weekend but we haven’t come to a conclusion yet.”

Seven-time world champion Lewis Hamilton is also likely to have to take a fourth power unit before the end of the year, and the same is true for his main title rival Max Verstappen.