Belgian GP: Valtteri Bottas to start at the back of the grid due to Mercedes engine change penalty

Valtteri Bottas will start the Belgian GP at the back of the grid after taking Mercedes' new upgraded engine.

Mercedes have brought their 'Spec Three' power unit to Spa but while Lewis Hamilton will use the upgrade penalty-free, Bottas had already reached his maximum allowance of engine components for 2018 and has therefore been penalised.

Renault's Nico Hulkenberg will join Bottas at the back of the grid after also reaching his engine parts limit, the FIA have confirmed.

Bottas has taken all six elements this weekend, while Hamilton has a new Internal Combustion Engine (ICE), Turbo Charger, MGU-H and MGU-K.

Mercedes' customer teams, the newly-named Racing Point Force India and Williams, have also fitted the new engine.

Bottas was optimistic about his chances despite the pending penalty, telling reporters on Thursday: "I think Spa would be one of the best places to take it as it is one of the easiest places to overtake."

Hamilton, meanwhile, is looking forward to the development battle between Mercedes and Ferrari with both title rivals introducing their third engines of the season this weekend.

Ferrari trialled their new power unit on the customer Haas and Sauber cars in Hungary, and its successful debut means both Sebastian Vettel and Kimi Raikkonen will use it in Spa.

Vettel has taken a new ICE, TC and MGU-H, while Raikkonen has the upgraded ICE.

FIA's confirmed engine changes
Drivers with new ICE
Lewis Hamilton, Valtteri Bottas, Sebastian Vettel, Kimi Raikkonen, Sergio Perez, Esteban Ocon, Lance Stroll, Sergey Sirotkin, Nico Hulkenberg, Carlos Sainz, Stoffel Vandoorne

Drivers with new turbocharger
Hamilton, Bottas, Vettel, Perez, Ocon, Stroll, Sirotkin, Hulkenberg, Vandoorne

Drivers with new MGU-H
Hamilton, Bottas, Vettel, Perez, Ocon, Stroll, Sirotkin, Hulkenberg, Vandoorne

Drivers with new MGU-K
Hamilton, Bottas, Vettel, Perez, Ocon, Stroll, Sirotkin, Hulkenberg

Drivers with new Energy Store
Bottas, Ocon, Stroll, Sirotkin, Hulkenberg

Drivers with new Control Electronics
Bottas, Perez, Ocon, Stroll, Sirotkin, Hulkenberg

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