Lando Norris hailed one of his best wins after conquering the weather in São Paulo a week after losing his status as world champion.
The British driver claimed his third win in a tricky season, passing Kimi Antonelli when the new title holder spun out from the lead in cold and slippery conditions.
Norris never looked back and crossed the line 14.6 seconds clear of Max Verstappen, who completed another stunning comeback drive from the back of the Interlagos grid.
The 26-year-old's only mishap of the day came as he celebrated his win with his trademark slamming down of the champagne bottle on the podium, only for it to shatter in his hands.
But Norris was toasting his victory after the race, saying: "It's up there [with my best] in terms of challenge to achieve. Not been easy for all reasons possible.
"Conditions, weather, important to not make mistakes. A lot thrown at everyone on a day like today, but probably our best race in terms of execution.
"I forced Kimi to push, he went into a mistake I could capitalize on. From my side not making any mistakes which is so easy to do. Great performance from the team."
Pole-sitter Norris lost the lead to Antonelli off the line in damp conditions before also dropping a place to Racing Bulls' Liam Lawson at Turn Two.
"I probably can't say [how I felt] or I will get a fine!" Norris added.
"I wasn't too pleased, but I knew things could easily change and a lot could happen."
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Verstappen started 21st, a place behind Lewis Hamilton after engine penalties for the pair. Hamilton soared to ninth after lap one, while the Dutchman soon ignited and was charging through the field.
He won this race from 17th in 2024 and was showing similar brilliance in the wet again, roaring past Hamilton as he closed in on the leading pack.
Norris reclaimed the lead having closed by pitting for soft tires a lap earlier, with Antonelli complaining of "something weird" with his car before he spun at Turn One.
He was off again as Verstappen progressed and Isack Hadjar also cruised through on his way to finishing third.
Antonelli allowed teammate George Russell through to come home fifth, with both Mercedes struggling with tyres on the day they clinched the constructors' title.
"I am very disappointed for the race, very angry to be fair, but I put that to the side for now because we clinched the title for the team. I am very happy for them," Antonelli said.
"Disappointing because we were on for the win, once I got temperature I had rhythm. I don't know why I lost the rears so quickly. We lost the race there."
Russell's hopes of a podium were undone when he spun on the exit of the narrow pit lane after his first stop, dropping him down to eighth.
Norris remains sixth in the championship but closed to within five points of fifth-placed Charles Leclerc as he moved towards the scrap for second, with Verstappen now 17 points clear of third-placed Russell.
The McLaren driver is pleased with the team's progress as they look towards 2027 but knows there is more to come.
"It is about good strategy, good pit stops, but I had a car I could fight for a win with today," Norris added.
"As much as we are happy, we are not as happy as we could be but we know we are not at the level we need to be yet. We are getting there slowly but we have work to do."