Red Bull advisor Helmut Marko did not mince his words in criticising Renault after Friday practice for the Australian Grand Prix.
Daniel Ricciardo was forced to sit out the whole of FP2 following a power unit problem in the opening session, while Toro Rosso also hit issues. Marko said the drivability of the power unit is "significantly worse" than a few weeks ago, while also annoyed by battery issues which affected Max Verstappen.
"The power unit broke after 50 kilometers which is incomprehensible, especially as the internal combustion engine cannot be repaired and we are only allowed four units for the entire season," Marko told Auto Motor und Sport.
"The engine's drivability is also significantly worse than in testing. We wanted an improvement and we have taken a step back. The gap to the top now is frightening."
Team principal Christian Horner was also openly discontent with the situation following the first day of running.
"In spite of Renault's promises to increase performance over the winter, the engine's actual power is the same as we had in Abu Dhabi last year," Horner said.
Click here for Friday's gallery from the Australian Grand Prix