With rain lashing the circuit, Hamilton’s victory was set up at the first turn, when a blazing start allowed him to sweep around the outside of the leading four cars.
It proved a lucky escape – pole-sitter Sebastian Vettel and his Ferrari teammate, Kimi Räikkönen, caught Red Bull Racing’s Max Verstappen in a pincer movement as the trio lunged towards the first-turn apex.
All three cars were fatally damaged on impact. Räikkönen lost control of his car and careered back into Verstappen, ending both of their races in the turn-one run-off, while Vettel limped a further two corners before tripping over fluids leaking from his own car.
Ferrari and Verstappen blamed each other for the crash, but a stewards investigation found no driver was predominately at fault.
Ricciardo followed Hamilton closely from the site of the wreckage, and the pair engaged in a tense race-long duel.
Three triggers presented themselves to Red Bull Racing in the strategic fight to overcome Hamilton.
The first was the lap-11 safety car, deployed to clean up Daniil Kvyat’s car from its place embedded in the barriers.
Ricciardo switched to a new set of intermediate tyres, but Mercedes opted not to stop Hamilton from the lead.
The new tyres ought to have given Ricciardo a decisive pace advantage over Hamilton’s older rubber, but the Briton was unperturbed by the Australian at the restart, rapidly rebuilding his gap.
The second trigger was the transition window from intermediate tyres to dry-weather slicks, but neither Ricciardo nor Hamilton were willing to be the first to change.
Haas’s Kevin Magnussen pioneered the dry-weather rubber, making the switch on lap 25, and Ricciardo pulled that trigger four laps later, but the ultrasofts took too long to warm up to give him any meaningful advantage over Hamilton, who made his own stop one lap later to hold the lead.
The gap between the two stood at around eight seconds, but the final trigger – a lap-38 safety car deployed to recover Marcus Ericsson’s stopped Sauber on Anderson bridge – presented a potential third opportunity for Red Bull Racing to jump Mercedes.
Ricciardo had an advantage of more than 20 seconds to Valtteri Bottas in third, which could have enabled him to make a pit stop without losing position.
The team, however, neglected to pit the Australian, and when Hamilton blitzed the restart by putting 2.2 seconds between him and Ricciardo after one lap, the race was effectively over – Hamilton had won his 60th Formula One grand prix and, with six races to go, put one hand on the championship.
“I really want to congratulate my team,” he said. “It’s amazing points for the team.
“Yesterday we struggled – we had no idea what was going to happen today – but we tried to stay focussed and tried to get ahead.
“God blessed me today for sure. I capitalised obviously on the [first lap] incident. Who would’ve know that would happen?
“Really unfortunate for the Ferraris, but a great result for the team.”
Hamilton said he was knew victory was on the cards as soon as the rain hammered down before the start of the race.
“As soon as it rained I knew where I was going to finish,” he said. “I knew I had the pace when it rains. Today, raining – those are my conditions.”
Ricciardo was disappointed his car was unable to challenge the Mercedes after demonstrating blistering pace for most of the weekend.
The Australian said after practice and qualifying that he expected to be able to dominate the race, but said he was pleased to collect his fourth consecutive Singapore podium.
“I can’t win the bloody thing!” he exclaimed on the podium. “I’m trying; I like it around here.
“Today we didn’t have that Friday pace we showed in practice to have the pace on Mercedes.
“I’m a little bit disappointed to miss out on the win, but I’m grateful and happy for another podium.”
Valtteri Bottas finished an anonymous third after a weekend off the pace of his victorious teammate.
The Finn said he had no confidence in the car after qualifying, but as the wet conditions transitioned to dry Bottas was able to threaten for second place.
“It was for us very good damage limitation today,” he said. “We definitely got lucky, but I have to say the car was working better than expected today.
“Personally I struggled in the wet with the pace, but in the dry it was pretty good – from time to tie I could put pressure on Daniel [in second].”
His podium place puts him just 23 points behind Vettel in the title standings, however – a smaller margin than that between Vettel and Hamilton.
“There’s still plenty of races to come and plenty of opportunities – definitely Sebastian is the next target.”
Mercedes holds a 102-point lead over Ferrari in the constructors standings with six races remaining.
The Formula One world championship continues in two weeks with the back-to-back Malaysian and Japanese grand prixs.