Formula One champion Lewis Hamilton gave Mercedes their 100th pole position at the Brazilian Grand Prix on Saturday while Ferrari's Sebastian Vettel qualified second and was reprimanded and fined for a weighbridge incident.
The pole, in a rain-affected session at Interlagos, was a record-extending 82nd of Hamilton's career and his 10th of a season that has already seen the Briton clinch his fifth world championship.
Mercedes will seal the constructors' title on Sunday unless Ferrari outscore them by 13 points.
Hamilton's team mate Valtteri Bottas, who was on pole in Brazil last year, qualified third with Ferrari's Kimi Raikkonen fourth on an all-Finnish second row.
"That was a tough qualifying session," gasped a delighted Hamilton, who had never previously managed to take a pole in a season after winning the title with races to spare.
"The weather was going up and down and we didn't really know what to expect. Obviously Ferrari are incredibly quick this weekend.
"I didn't know whether or not I had the pole. The last lap wasn't that great, if I'm honest. I had a bit of understeer in a few places," added the Briton, who has five stars and the late Brazilian Ayrton Senna's design on his helmet.
Hamilton and Vettel provided the main talking points of the session, with the former fortunate to escape the immediate attention of the stewards after nearly colliding with the Williams of Russian Sergey Sirotkin.
Raikkonen also had to swerve to avoid him in another incident.
Vettel's summons by the stewards was inevitable after he was called in for weighing at a critical point in the second phase just as the rain began to fall, making it crucial to get in an early timed lap.
With a cone barring access to the weighbridge, he drove into it and then gesticulated angrily for officials to hurry up, before driving off again in a breach of the regulations.
The governing FIA said that by keeping the engine running he had made it hard to get a stable result and by driving off rather than being pushed he had also 'destroyed' their equipment.
"They shouldn't call us when the conditions are changing like that, I think it's unfair if somebody gets pulled in. I wanted them to hurry up," said Vettel.
He was later fined $25,000 and reprimanded, but kept his grid position.