Red Bull technical chief Adrian Newey has given some insight into how Sebastian Vettel deals with pressure after the Ferrari driver slipped further behind Lewis Hamilton in the drivers' championship in Singapore.
Vettel now trails Hamilton by 40 points in the standings after the Mercedes driver took his fourth win in five races at the weekend.
Newey worked with Vettel throughout Red Bull's four seasons of championship successes with the German driver and believes he is susceptible to pressure.
"He works incredibly hard and is sometimes too dogged -- hardly anyone is more self-critical than he is," Newey told Bild am Sonntag. "If he has a weakness, then it's that sometimes he makes stupid mistakes that happen in the heat of the moment. If he leads a race, he is almost unbeatable. But in direct duels he sometimes slips up.
"In sports, but also in life, people deal differently with pressure. For a racing driver this can be particularly difficult. In the car, he is not only responsible for himself, but he has the entire team in the garage on his shoulders.
"Some drivers do not care; take the Finns Kimi Raikkonen and Mika Hakkinen, for example. But then there are also drivers who, just at the end of a season, when it comes to the world championship, feel the pressure weighing down on them. The harder a driver works, the more he feels the pressure. "
Newey said Vettel will have to rely on Hamilton encountering problems in the remaining races in order to get back in the title fight.
"If he's going to manage it, he needs at least one retirement from Lewis. Otherwise it will be damn hard."
Red Bull team boss Christian Horner agrees it will be difficult for Vettel to turn the situation around, but drew comparions with 2012 when Vettel won the championship for Red Bull despite being 39 points behind with seven races remaining.
"It looks like Lewis is in the driving seat now, so he has just got to be consistent until the end of the year," Horner said. "It is going to be an uphill battle for Ferrari to get themselves back into it.
"Usually Sebastian is very good under pressure so he certainly won't give up. He was 40-odd points down before in 2012, but obviously it will be disappointing for him to lose out to Lewis in Singapore."