Carlos Sainz will start the Monaco Grand Prix from the pit lane after missing a call to the weigh bridge during Q1 in qualifying.
Cars are called for random weigh checks during practice and qualifying sessions and Sainz did not see the light telling him to stop. Instead he drove back to the garage where work was conducted on the car, thus breaching Article 26.1 of the sporting regulations.
He had qualified eighth on the grid and the penalty is made all the worse by the lack of overtaking opportunities at Monaco.
Speaking before the penalty had been issued, Sainz said: "The red light [for the weighbridge] is in a place where I could not see it easily. When I went into the pit-lane I saw it too late but, the next time, I saw it okay, so I don't think there should be too much of a problem. I mean, I couldn't see the weighbridge and I think the position of the light needs to be changed."
Romain Grosjean will start 15th after he received a five-place grid penalty for a gearbox change (and then moved up one slot with the news of Sainz's penalty). Grosjean's gearbox was damaged at the Spanish Grand Prix and under the regulations gearboxes have to last six races, with Monaco being the sixth for Grosjean's.