Sochi - Lewis Hamilton has avoided a penalty and will start in 10th place on the grid for Sunday's Russian Grand Prix after a new fuel system was flown out by private jet.
The team worked through the night to repair his power unit knowing he would have received a penalty if they had installed an older fuel system than that used on the car on Saturday (April 30).
This was a new system for the Russian race and no identical spares were available at the Sochi Autodrom - a situation that forced the team to fly a replica new one to Russia, or revert to an older specification.
In a statement, the team said it had worked to give Hamilton the best possible chance of a points-scoring result after his run of bad luck had continued on Saturday when he suffered a second successive engine failure in qualifying.
The statement said: "Our entire approach has been guided by ensuring we do not break the Parc Ferme regulations so Lewis can start P10 today, rather than from (the) pit lane, to give him the best chance of a strong finish.
"The complication was in ensuring that we replaced with parts of the same specification, as we introduced an upgrade here for all eight power units, but did not have spare components on site.
"So we had to fly out a fuel system on a chartered jet yesterday evening, arriving here in the early hours, and the spare engine was then kitted with these parts during the night (the spare engine is not covered by Parc Ferme rules).
"When the car came out of parc ferme this morning, the spare PU was fitted and has now fired up successfully in the garage."
The Mercedes team posted an update on their Facebook page: