McLaren pair to use two engines each for Belgian GP

McLaren are to take an unusual step at the Belgian Grand Prix by using two new engines over the race weekend for each of their drivers, Fernando Alonso and Jenson Button.

The team will use a newly upgraded Honda power unit in both cars for Friday practice before switching it out for a brand new unit of the same specification on Saturday.

The first unit will mark the seventh change for both Alonso and Button, meaning the pair will drop down the order. Button will likely face a five-place grid penalty as he's already used a seventh turbo charger and MGU-H, whilst Alonso will drop ten-places as he's yet to use a seventh of any component.

However they will both use an eighth power unit on Saturday through to Sunday, allowing Honda the chance to conduct a thorough analysis of their upgraded engine.

A double change would have previously seen them forced to start from the back of the grid, whilst also incurring time penalties which must be served during the race.

However the engine penalty rules were amended last month after claims they were too harsh.

Therefore Alonso and Button will likely be forced to start at the back of the grid in Belgium, but they won't face any further penalties and they will have the added benefit of having two new (or nearly new) engines to use over the next couple of races, without penalty as they can swap back to their seventh unit freely.

Alonso described the move as "sacrificing" a race they're likely to struggle at for a better chance of success later in the season - likely Singapore.