Ferrari believes it was an electronics issue that sent Charles Leclerc into the wall on the Brazilian Grand Prix formation lap, and admitted it reoccurred almost immediately while he was trying to make it back to the pits for repairs.
Leclerc should have started the race second to Max Verstappen's Red Bull, but spun across the run-off area and into the barriers at the long Ferradura right-hander on the parade lap.
He immediately cited a car problem over team radio, saying: "No! I lost the hydraulics, I lost the hydraulics. Why am I so unlucky?"
Once back in the pits he revealed Ferrari had found a deeper problem, saying "there was an engine thing that made me lock the rear wheels and then I went into the wall and couldn't do anything." The first he'd known of it was "when I lost the steering wheel and I went straight".
Team principal Fred Vasseur didn't got into explicit detail about what had gone wrong, but suggested it had been a complete shutdown of the car's systems that led Leclerc unable to control it.
"It's a system issue where the system shut off the hydraulics and engine," said Vasseur.
"The result of the [issue] from the system we don't know yet because the car is not back, but it was more an electronic problem."
Leclerc initially drove away from the tyre wall with front wing damage and looked like he might be heading back to the pits for repairs.
But then he parked behind the barriers shortly afterwards.
Vasseur said Leclerc had "started to switch off and switch on" to try to revive the car, but "the issue is he made 30 metres and then found himself in the same situation so it was better to stop".
"[There was] no way to recover," he added.
Asked how Leclerc was feeling, Vasseur joked "yeah good, we go for the party tonight!" before making the more serious point that this was a particularly painful loss because Ferrari had more reason to feel confident about its race pace than usual as it had largely sacrificed the sprint to put itself in a better tyre position for the main event.
"It's very frustrating for Charles and for the team," he said.
"But the issue is that strategically over the weekend we put all the effort into the long run to save tyres - we didn't use new tyres for the short one, we didn't use new tyres for the race of the short one, we put everything on the long one and we didn't take the start."
Though Carlos Sainz took the remaining Ferrari to sixth, it was a huge missed opportunity on a weekend when Mercedes - the team's rival for second in the constructors' championship - struggled for pace so much.
Ferrari gained only four points on Mercedes in the grand prix and goes into the final two rounds 20 points behind.
"We were in a good position today and it's a missed opportunity because we were catching up Mercedes a little bit over the weekend but with Charles on the front row with three sets of new tyres it could have been much better," said Vasseur.
"We still have two attempts in Vegas and Abu Dhabi. Vegas could be a chaotic one, and if we have the same pace as this weekend and Mercedes has the same pace as this weekend we have an opportunity."