McLaren have revealed that it was an anti-roll bar failure that robbed Lewis Hamilton of his pace in the Korean Grand Prix.
Hamilton had been running in fourth place after the first round of pit stops when he reported a lack of front-end downforce to his team.
Although it was thought that his tyres may be graining, the McLaren driver lost pace and positions as the race continued, eventually finishing a distant tenth.
"We had a rear anti-roll bar failure around lap 18," revealed sporting director Sam Michael.
"We were telling Lewis 'everything is safe but you're going to have to manage it for the rest of the grand prix and he did the best job he could.
"It's very difficult to go into detail on the radio about exactly what the failure was. The only thing Lewis needs to know is the car is safe and you are going to have a difficult afternoon trying to drive it.
"Until we get the car apart we can't tell what the problem is. We need to look at our processes and find out what the exact failure is."
Hamilton's car issues coupled with Jenson Button's first lap retirement meant McLaren scored just one point in Korea and dropped to third in the Constructors' Championship. With four races remaining the Woking team is six points behind Ferrari and 83 adrift of Red Bull.
"We need to at least recover back to second place in the next race," said Michael.
"We only need Red Bull to have a bad race and we have a one-two and we're back in the game. We won't give up until the end."
Vettel Takes The Korean Win & Title Lead
Any reproduction, publication or redistribution of this material without the written agreement of 365 Media Group is strictly forbidden.