Oscar Piastri powered to victory at the Bahrain Grand Prix on Sunday from George Russell's Mercedes with the Australian's McLaren teammate Lando Norris in third.
Pole-sitter Piastri kept his calm in an incident-packed race to give McLaren their first ever win in Sakhir at their 21st attempt.
Max Verstappen's trying weekend at the desert track ended with the four-time world champion only managing sixth place.
Norris leads the drivers' standings on 77 points, with Piastri overtaking Verstappen and into second ahead of next weekend's race in Jeddah.
"That should be one hell of a party tonight. Mega weekend everyone. That was pretty damn fun," Piastri said after marking his 50th start in perfect style.
Taking the chequered flag under floodlights on a balmy Sunday evening in the Gulf kingdom was just reward after a weekend he had dominated, both in practice and in qualifying.
Despite an incident-packed race behind him, Piastri, who also won in China last month, crossed the line 15.499sec clear of Russell, who was under investigation for an issue with the DRS (drag reduction system), meaning he could take a five-second penalty.
Charles Leclerc came in fourth with his Ferrari teammate Lewis Hamilton fifth ahead of Verstappen and Pierre Gasly earned Alpine's first points of the year at the fourth attempt.
Rounding out the top 10 were Esteban Ocon (Haas), recovering from a big smash in qualifying, Yuki Tsunoda in the second Red Bull, and Ocon's teammate Oliver Bearman.
As the sun dipped down over the Gulf the lights went out on the fourth race of the season with pole-sitter Piastri getting his gloves off early to fend off Russell's Mercedes to turn one.
Norris got a dream getaway, jumping from sixth to third to muscle back into contention after a disappointing qualifying.
That was until a message from FIA race control warning they were investigating the McLaren man for being "out of position" at the start.
As the officials deliberated Piastri was posting the fastest lap to pull over two seconds clear of the chasing Russell.
The anticipated news then came through of a five-second penalty for Norris, and he was quickly 'boxed' to serve the sanction in the pits.
He resumed 14th with a fifth of the 57-lap race completed.
After pitting, Piastri emerged with Ferrari duo Leclerc and Hamilton in front of him, as Norris scythed his way through the pack up into sixth.
The Australian was soon back in front when the two Ferraris were summoned in for a change of footwear.
Verstappen has not cut a contented figure in Bahrain, grumbling to his pitlane: "I can't even brake anymore, it's ridiculous."
At the halfway point Piastri led from Russell, with Leclerc nipping past Norris into third.
With the safety car then deployed to pick up debris at turn three Piastri took the opportunity to dive into the pits for a 'free' stop', followed by his closest pursuers.
The restart was manic, with mayhem behind Piastri as Norris muscled past Hamilton who pointed out "Lando passed me off the track".
Norris gave the position back, but just up the road sailed past the seven-time champion.
Entering the business end of the race, Piastri turned the screw to pull clear of Russell as Norris lunged past Leclerc.
There was no-one happier in the crowd than the ruler of Bahrain, King Hamad Bin Isa Al Khalifa, whose sovereign fund owns McLaren.
