"Adrian has gone back to the drawing board, definitely," team newcomer Daniel Ricciardo, on duty on Thursday, said.
Red Bull had initially pointed the finger at engine supplier Renault, and the French marque duly admitted it has had problems with all of its customer teams, including Toro Rosso and Caterham.
But Marko confessed before departing on Thursday that the latest problems are also Red Bull's making. Paddock rumours suggest Newey has pushed his famously tight packaging too close to the limit in a new era where cooling is a major hurdle.
"I guess now there's only so much he (Newey) can do at the track and I think he's pretty happy working at his office in Milton Keynes," added Ricciardo.
Red Bull is expected to try to get the RB10 running on Friday, the final day of the Jerez test, but the real attention will be ensuring the car is in working order for the crucial final two tests, in Bahrain.
"I think the break before Bahrain is going to help the team a lot," said Ricciardo. "Even if tomorrow doesn't go to plan, we still won't be worried.
"Time is still on our side. Even if we go to Melbourne with whatever (issues), it's a long season. These guys know how to win and I'm sure we'll sort it out," he added.
Undoubtedly, Ricciardo is putting his characteristically-smiling tilt on serious trouble for Red Bull.
There are rumours that, before Newey left, he had a "heated" exchange with Renault's Rob White -- each accusing the other of being most to blame for the situation.
And Red Bull's culpability seemed clearer on Thursday, when sister team Toro Rosso's Jean-Eric Vergne said a Renault fix had given the new STR9 a "massive step forward" overnight.
Bernie Ecclestone, nonetheless angry at the Jerez testing 'farce', sees some upside to the situation.
"The good thing is that the season could be extremely interesting -- really unpredictable, and that is the exciting thing," he told the Daily Mail.
Williams' Felipe Massa agrees that the 2014 revolution has given F1 a total shakeup.
"As I drove around, you could see these major differences between the cars," the Brazilian is quoted by Finland's MTV3.
"I'm not talking about performance, I mean how the cars are braking and how they're coming out of the corners. It seems as though there are three categories of cars on one track -- Mercedes, Ferrari and Renault. Even the sound is different," he explained.