BUDAPEST: Red Bull boss Christian Horner blasted his team's engine supplier Renault on Sunday after Dutch driver Max Verstappen retired from the Hungarian Grand Prix just five laps into the race.
Verstappen's expletive-laden reaction over the radio was largely bleeped out for the worldwide television audience but Horner expressed his dismay in a more measured but equally forceful manner.
"Sometimes words betray you," the Briton told Sky Sports F1 television.
"Cruel luck for Max, it's an engine issue. I suppose no surprise really," he added.
"I'm not going to get drawn into saying too much. We pay multi-millions of pounds for these engines and for first class, or state-of-the-art, product and you can see it's quite clearly some way below that."
Horner said he would let Renault F1 managing director Cyril Abiteboul "come up with the excuses afterwards."
Red Bull are ditching Renault at the end of the season and switching to Honda from 2019.
Renault powered the former champions to drivers' and constructor's titles for four years in a row between 2010 and 2013 but the relationship frayed in the current V6 turbo hybrid era.
Red Bull had fancied their chances in Hungary before the weekend but rain in qualifying dented their hopes, with 20-year-old Verstappen starting seventh and Australian Daniel Ricciardo back in 12th.
Ricciardo, race winner in Monaco, took grid penalties in Germany last weekend -- starting at the rear of the field -- to give himself the best chance in Hungary but retired from that race due to a power unit problem.
It subsequently emerged that the Australian had been unable to take all the new components Red Bull had wanted because Renault made only three of the six items available. The normal strategy would have been to change everything.
"Engine failure can happen at any time, even with a new engine, unfortunately, it can happen, as happened in the past," Abiteboul told motorsport.com after that race at Hockenheim.
Verstappen, the youngest ever race winner in Formula One history, has an army of Dutch fans with thousands travelling to Budapest to cheer him on.