Mercedes has confirmed Lewis Hamilton has taken a third and final power unit change ahead of the Belgian Grand Prix, consolidating his grid penalties and ensuring he starts at the back of the grid.

The championship leader was always expected to start towards the back of the grid after Mercedes changed his engine outside of the permitted allocation before the weekend. As a result, it has decided to complete two more changes to increase its pool to the end of the season, consolidating his penalties but giving him no added disadvantage.

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With the final change landing him 25 positions worth of grid penalties - on top of the 30 he had already notched up -, the total 55 positions of grid penalties all-but-guarantees a last place start.

As a result, Mercedes is unlikely to send Hamilton out for a representative qualifying run in an effort to preserve engines and tyres. Instead, he will complete a lap good enough to get him within the 107 per cent marker, before sitting out the remainder.

Fernando Alonso is expected to join him on the back row after suffering an engine change that notched up 30 positions worth of grid penalties.

Previously, time penalties were applied should teams suffer penalties that cannot be applied by a grid drop, but this has been axed for 2016, hence the decision to complete multiple engine changes at a time.

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