A dreaded 10-place grid penalty for exceeding an authorized number of power unit elements looks almost inevitable for Red Bull Racing's drivers this season.
Renault have announced that all four Red Bull and works Renault drivers have had their cars fitted with a fourth MGU-H element.
As a reminder, a fifth version would exceed the allocated amount permitted over the course of the 20-race season, and automatically trigger a 10-place grid penalty.
The MGU-H replacements yesterday were the result of a precautionary measure decided by Renault following an issue on Daniel Ricciardo's car.
"We tried something, it was really on the limit of introducing or not introducing that modification," said Renault Sport F1 boss Cyril Abiteboul.
"Indeed it created an issue on one of the cars only, Ricciardo's, and that issue meant that we took the decision to change all the others.
"We tried something and we had the capacity to react overnight, and hopefully this will not repeat again."
Abiteboul insisted however that under F1's regulations, a previously used MGU-H can be modified and returned to race weekend use.
"The issue we had on the MGU-H yesterday we will be able to patch or modify back at the factory and use it again because it's peripheral, it's ancillary."
Christian Horner said the change will inevitably lead to grid penalties sooner or later. But the Red Bull boss also pointed to Sebastian Vettel's use of four turbos this season, which also places the Ferrari driver on the penalty bubble.
"It's not ideal," he told Motorsport.com. "But just looking at Sebastian's allocation, it looks pretty similar to be honest. It is what it is.
"We're not quite at the halfway stage yet, but we'll do our best to manage it between now and the end of the year. A couple of the old ones are still alive."