Lewis Hamilton has been stripped of pole position for the Spanish Grand Prix.
Hamilton, 27, set the fastest time in qualifying but failed to return to the pits.
After undertaking a similar action after taking pole for the 2010 Canadian Grand Prix, his McLaren team was fined $10,000 and the rules changed.
Article 6.6.2 of the regulations state that 'Competitors must ensure that a one litre sample of fuel may be taken from the car at any time during the Event.
Except in cases of force majeure (accepted as such by the stewards of the meeting), if a sample of fuel is required after a practice session the car concerned must have first been driven back to the pits under its own power'
The alteration means that Pastor Maldonado takes his first career pole and the first for Williams since the 2010 Brazilian Grand Prix.
Maldonado had excelled all weekend yet his original front row start was nevertheless a surprise for the Formula One fraternity.
The result moves home favourite Fernando Alonso to the front row; the Spaniard last started at the front in Canada last year.
Lewis Hamilton will start from 24th for tomorrow's race.