Bridgestone blames McLaren Lewis Hamilton's title hopes exploded in Shanghai because McLaren ignored the advice of tire experts for five crucial laps.
Until now it was thought the 22-year-old sensation and his team pushed their luck just a lap or so too far. But well-placed sources have revealed the scale of the McLaren muddlers' miscalculation in the biggest race of the year.
The blunder could yet cost Lewis a world title and his place in history as Formula One's first rookie champion.
Tire suppliers Bridgestone are furious that the advice of their experts was ignored in such changeable track conditions, and in such a crucial race. Given the variable weather, Hamilton's team were advised he should pit on lap 26.
Yet despite evidence of dramatic tire wear on pitlane monitors, Hamilton's own radio reports of vibration and all the car data being received in the pits, the team kept him out on the circuit until lap 31.
By then, it was too late.
He was only attempting to negotiate a 40mph left-hand bend at the start of the entry road to the pitlane, but skidded off the tarmac when he braked because his exhausted tires had nothing more to give.
His McLaren-Mercedes beached on a ridge of sand, sending the championship to a three-way showdown at the final round with Kimi Raikkonen and Fernando Alonso. Bosses at Bridgestone, who supply all the teams' tires, are fuming.
"There are questions being asked high up the company in Japan," said a paddock source. "The top brass are demanding an explanation because they are just amazed by what has happened." Mirror.co.uk