The Frenchman has been given the penalty for clashing with Sam Bird and Davide Valsecchi in the braking zone for Turn 2 a the start of Sunday's sprint race in Valencia.
The race one winner had started eighth, and he ran into the back of Bird and hit the right hand side of Valsecchi's car as he tried to go between them into the first braking zone.
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While the DAMS driver's contact with Valsecchi was only minor, Bird was forced to pit for repairs. Grosjean then spun his damaged car at Turn 5 and was collected by Rodolfo Gonzalez and Charles Pic.
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