Max Verstappen had no explanation for the mistake which saw him lose pole position at the Saudi Arabian Grand Prix.
Verstappen seemed to have pole in the bag with a lap that was right on the limit at the end of qualifying, including a near miss with the wall at Turn 2.
He was over 0.2s up on title rival Lewis Hamilton when he locked up and hit the wall at the final corner in what one of the most dramatic moments of the season so far.
Verstappen will start Sunday's race from third, behind Hamilton and Valtteri Bottas, unless the crash has damaged his gearbox. A change would drop him five places down the order.
"Yeah, it's of course terrible," Verstappen said after the session. "But that was generally a good qualifying.
"It was a bit hard of course to switch on the tyres here on the street circuit, but I knew the pace was there and it showed in the last segment.
"I don't really understand what happened, but I locked up and I still tried to of course keep the car on the track, try to finish the lap but I clipped the rear and had to stop.
"P3 is a bit disappointing of course today, knowing what lap I was on. Nevertheless, it shows that the car is quick and let's see what we can do in the race."
On the chance of a penalty, Verstappen said: "I don't know. I immediately stopped, so let's see."
Red Bull boss Christian Horner said he has no doubts Verstappen will put the mistake behind him and be back on form for Sunday's race.
"It was looking like the lap of the year. It's a great shame," Horner told Sky Sports.
"He just grabbed the front into the last corner there. You're trying to keep the momentum... He could see on his dash he was more than a quarter of a second up going into the corner and unfortunately he's run out of road.
"Pretty brutal, let's hope the gearbox isn't damage and we'll see what we can do tomorrow."
Verstappen has an outside chance of winning the championship on Sunday, although his qualifying mistake made that seem even less likely. If Verstappen outscores Hamilton by 18 points, he will win the championship.