Christian Horner has described the Renault power unit as "undriveable" after a disappointing Australian Grand Prix.
Daniel Ricciardo was limited to sixth place in the opening race of the season, lost a number of places at the start as numerous cars accelerated past the Red Bull despite a solid launch. Having already criticised Renault this weekend, Horner highlights the run to the first corner as proof of how bad the power unit is.
"It’s been a tough weekend and a very tough weekend for Renault," Horner said. "The engine is quite undriveable and you can see and hear that from the comments that the drivers are making. The clear evidence was at the start when Daniel got a pretty reasonable start before drivability came in and you can see the holes that are in the power delivery. A lot to be done."
Horner was even willing to quote figures to highlight the deficit Renault is facing.
"We’re probably 100bhp down on Mercedes at the moment. I think [Ricciardo] got everything out of the car."
And Horner says Renault needs to urgently react to its current approach, saying the engine manufacturer is "in a bit of a mess" at this stage.
"After this weekend it’s important that we regroup with Renault and try to offer support where we can because it’s obviously in a bit of a mess at the moment. We need to understand things quickly. Across the four cars we have had two engine failures - one within five laps – and a whole bunch of reliability problems. It’s not the start Renault can afford to have."
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