Mercedes has confirmed it upgraded its power unit over the summer break with both Lewis Hamilton and Nico Rosberg making use of an updated engine for the Belgian Grand Prix.

The manufacturer revealed it has spent five tokens from its remaining allocation, though refused to give more detail about which areas have been focused on. It is left with six tokens to spend this year, though a spokesperson stressed it is under no obligation to use them.

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The German firm confirmed the upgrade is also available to customers Force India, Williams and Manor but having taken new engines at Hockenheimring they will likely wait until incorporating the updates.

Mercedes' upgrade comes after Honda used seven tokens updating its power unit for McLaren.

RESULTS: Belgian Grand Prix - Free practice results (2)

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