World champion Max Verstappen rekindled his title defence on Sunday with an accomplished victory ahead of team-mate Sergio Perez in a dominant one-two triumph for Red Bull at the Emilia Romagna Grand Prix.
In a rain-affected race, the pole-sitting 24-year-old Dutchman came home more than 16 seconds ahead of his team-mate as Charles Leclerc and Ferrari endured a disappointing day in front of passionate home support at the Autodromo Enzo e Dino Ferrari.
Leclerc, who started second on the grid, finished sixth after making a poor start and spinning in the closing laps while running third, allowing Lando Norris to take the final podium place for McLaren.
George Russell produced a stirring drive for Mercedes to come home fourth after starting 11th, fending off Valtteri Bottas's Alfa Romeo at the finish, while team-mate and seven-time champion Lewis Hamilton finished a distant 14th.
It was Verstappen's second win this season after Saudi Arabia, which has also included two retirements, and the 22nd of his career.
He reeled off a grand slam weekend with pole position, victory and fastest lap as well as victory in Saturday's sprint race.
He moved up to second in the title race behind Leclerc, reducing his deficit from 45 points to 27 to set up the prospect of an intense duel this year.
"Today, you never know with the weather how competitive you are going to be but I think we did very well and this one-two is very deserved," said Verstappen.
"The start was very important but afterwards, judging the conditions and when to swap to the slick tyres, because in the lead you have to always dictate the pace."
AlphaTauri's Yuki Tsunoda finished seventh ahead of four-time champion Sebastian Vettel in an Aston Martin, Kevin Magnussen of Haas and Lance Stroll in the other Aston Martin.
A morning downpour eased shortly before the race, leaving the track in a treacherously wet condition and the teams faced with a difficult choice on tyres and strategy.
For the packed crowds of 'tifosi' huddled on open grandstands and grassy banks, it was a disappointing day.
Verstappen surged into the lead from pole position.
- Hamilton lapped by Verstappen -
Leclerc, starting second, was passed by the Dutchman, Perez and Norris before Daniel Ricciardo in a McLaren tangled with Sainz at the first chicane.
It was a second consecutive early exit for Sainz after his misery in Melbourne.
The Spaniard was left beached in a gravel trap, prompting a first Safety Car intervention to recover the Ferrari while Ricciardo survived their impact to pit for fresh tyres.
After a fine start, Russell had risen from 11th to sixth behind Magnussen's Haas, while Hamilton made more cautious progress in 11th, having started 14th.
After several attempts, Russell passed the Dane at the Variente Alta.
On lap eight, Leclerc passed Norris for third at Tamburello, but faced a six seconds deficit to Perez as, in the pits, Fernando Alonso retired his Alpine, damaged in an early collision with Mick Schumacher's Haas.
Hamilton, who had been reluctant to pit, was impeded by Estaban Ocon's Alpine, but avoided a collision while Perez, who stopped on lap 19, managed to retain second place ahead of a charging Leclerc.
Ocon was given a five seconds penalty for his unsafe release.
By half-distance, Verstappen was cruising with a 10-second cushion ahead of Perez and Leclerc, frustrated in third.
On lap 41 came Hamilton's most humbling moment when he was lapped by Verstappen as he battled for 13th with Pierre Gasly's Alpha Tauri.
Leclerc pitted on lap 50 for softs, dropping to fourth behind Norris. Perez followed on 51, as Leclerc passed the McLaren and Verstappen one lap later, retaining a 13-second lead.
The Monegasque charged hard to pass Perez on lap 53, but spun off at Variante Alfa, damaging a front wing.
He pitted, re-joining eighth as Norris inherited third and Russell took fourth, resisting Bottas in the final laps.