Red Bull have written off the 2015 Formula One season, with team principal Christian Horner urging Renault to go all out with development in the hope of a strong campaign next year.
Horner has been liberal with his criticism of Red Bull's engine manufacturer Renault so far this year, as his team have struggled with engine reliability issues and a lack of speed to challenge the likes of Mercedes and Ferrari.
Red Bull's drivers Daniel Ricciardo and Daniil Kyvat finished seventh and 10th respectively at Sunday's Spanish Grand Prix, leaving them 172 points behind leaders Mercedes in the constructors' standings after five races.
"We are so far on the back foot with reliability anyway that, to be honest, this year is pretty much a write-off," Horner said afterwards.
"You just have to go for it [for the rest of 2015], even if they end up using 20 engines, it would be better to learn and make progress for next year. It would be far easier to make a fast engine reliable than to make a reliable car fast, so our philosophy has been to push performance.
"I think they [Renault] know what the deficit is. The question is how are they going to make that up. They have things in the pipeline and things for later in the year but it is all a work in progress.
"I think they are looking at different scenarios and solutions, but they haven't got a definitive direction yet. Hopefully they are homing in on it and things in the engine world take longer than in the chassis world."
Ricciardo's seventh-placed finish was just one spot off Red Bull's best result of 2015 so far, sixth from the Australian at his home GP and in Bahrain.
Even the ever-smiling 25-year-old hinted at Red Bull's inability to truly challenge the teams ahead of them in the constructors' championship - Mercedes, Ferrari and Williams.
"I am more satisfied today as we achieved everything we could and seventh was the maximum I could get out of the car," Ricciardo said.
"There were some parts of the race that were encouraging but we're still further off than where we want to be, but we'll keep pushing."