The Dutchman converted pole position successfully despite having to contend with the rigours of a wet race among the final third of the race, extending his stint on the medium tyres to cover off the looming threat of rain.
With a dry start to proceedings, the medium-shod Verstappen covered off any threat of a pass from Alonso on the hards at the start, and immediately began to cement his lead early on with a strong opening salvo of laps to build a buffer.
Alonso was unable to match his fellow two-time champion's laptimes in the first phase of the race, as worries over a puncture suggested that the Aston Martin was not handling correctly - although his team informed him that all was well when checking tyre pressures.
The lead reached 11.8s by lap 25, although this had shrunk slightly by the 30th lap, with the gap 10.6s over Alonso. At this juncture Verstappen had begun to close in on traffic as he was angling to lap the backmarkers - including team-mate Sergio Perez.
This allowed Alonso to cut the arrears as Verstappen attempted to barge his way through the rearguard action, despite Perez doing his best to make his fellow Red Bull driver's life easier.
The gap shrunk to 5.6s, but then began to grow once more as Alonso was now firmly ensconced in the tailback as Verstappen had largely cleared it.
Radio reports over the severity of rain began to intensify, and Red Bull elected to hold off pitting Verstappen to ensure he was well placed to take advantage of a well-timed pitstop.
As light showers grew into heavier rainfall, particularly in the middle sector, which prompted a number of backmarkers to bolt on the intermediate compound.
Alonso then pitted on the 54th lap, but Aston Martin made a lamentable decision to bolt mediums onto the Spaniard's car just as the rain continued to fall.
This prompted him to pit again on the following tour, along with Verstappen, to collect the intermediates - but the gap was well over 20s at this point.
Despite Alonso's best efforts to close the gap over the remaining 20 laps, getting it down to 17.8s at one point as Verstappen could not switch on his intermediate Pirellis as swiftly, the Red Bull driver grew in strength and continued to build his advantage.
Alonso's arrears continued to increase and he eventually had to concede, finishing almost 28 seconds behind at the chequered flag.
Esteban Ocon converted his third-place start into a third F1 podium, despite coming under heavy pressure from Carlos Sainz in the early stages.
Sainz and Ferrari had been attempting to goad Alpine into pitting Ocon early to gain track position, but the Anglo-French squad did not bite. On the 52nd tour, Sainz had his best shot at passing Ocon as the rain had emerged, but went off at the Nouvelle Chicane and had to give way.
Ocon then came under attack from Lewis Hamilton during the rain-hit phase of the race as the Mercedes duo had undercut the Ferraris, but the Frenchman held firm to keep hold of a podium place.
Hamilton finished fourth ahead of team-mate George Russell, who copped a five-second penalty for rejoining the circuit unsafely at Mirabeau; having slid off, he reversed and went into the path of a hapless Sergio Perez, who made contact with the Mercedes.
Nonetheless, Russell's advantage over Charles Leclerc ensured he kept fifth, as the Monegasque overtook team-mate Sainz as they were scrabbling around on medium tyres prior to their pitstop - and a double-stack to swiftly bring the SF-23s onto intermediates hurt Sainz further.
This put the Spaniard behind Pierre Gasly, whom he could not pass despite lingering behind his gearbox.
Lando Norris and Oscar Piastri completed the points, the McLaren duo making carbon-copy Turn 1 passes on Yuki Tsunoda on consecutive laps as the AlphaTauri driver struggled with his brakes.
Verstappen opened his championship lead to 39 points over Perez following the Mexican's miserable race, where he pitted five times having started last, and ultimately finished 16th.
F1 Monaco GP - Race results:
|Nyck de Vries
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