Lewis Hamilton under investigation by marshals after Brazilian GP qualifying

It is more precisely its DRS (the flap mounted on the rear wing of its single-seater which opens to gain top speed) which is in question because it would open more than the regulations allow.

If the marshals deemed that his car was out of order, the seven-time world champion would risk disqualification and a start from the back of the grid of the qualifying sprint race on Saturday.

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