Max Verstappen's bid for a record-extending 11th straight win faces a severe test in Sunday's "perilous" Singapore night race on the unpredictable Marina Bay street circuit.

The Red Bull driver's third world title in a row is only a matter of time but the Dutchman has never triumphed under the lights in Singapore, where tropical storms, intense humidity and concrete barriers all await.

Safety cars and red flags will almost certainly play a part too, with memories of an "incredibly messy" race in Singapore a year ago fresh in Verstappen's mind. Rain is again forecast for race weekend.

Verstappen was only eighth on the grid in 2022 after being under-fuelled in Saturday qualifying and a pre-race deluge saw him start poorly on the sodden track, dropping back five places.

He clawed his way through the field with the help of several safety car and virtual safety car periods, only to slither on to an escape road while trying to take fourth place, eventually rejoining and settling for seventh.

Red Bull teammate Sergio Perez kept his cool out in front to win ahead of Charles Leclerc in a Ferrari and keep the champagne on ice for a bit longer.

"It's better than eighth but it's not what I'm here for, not with a car like that," lamented Verstappen after the race. "It was just incredibly messy."

Verstappen leads Perez by 145 points in this year's championship and could clinch the world title with six races to spare at next week's Japanese Grand Prix.

Mercedes are second in the constructors' championship, a distant 310 points behind, with team boss Toto Wolff believing that Red Bull are on course to win all 22 races this season.

"I think they need to screw it up themselves," Wolff said after Verstappen's 10th win in a row at Monza a fortnight ago made it 14 out of 14 for Red Bull in 2023.

- 'One of the toughest' -

If they complete the clean sweep, Red Bull would eclipse the record of Mercedes in 2016 when Nico Rosberg and Lewis Hamilton won 19 of 21 races.

Red Bull team principal Christian Horner warned that the unique Marina Bay challenge could upset their perfect season.

"It's a street circuit, it's one of the toughest on the calendar. We saw last year how perilous it can be," said Horner.

"We'll just do our best to keep this momentum running.

"One day we're going to get beaten. It's just a question of when, and we've just got to make the when as far away as we can. 

"I think with every weekend that goes past there's more expectation to keep up this amazing run of results."

- Mercedes chance? -

Singapore lap times will be quicker this year because of construction work near the city-centre circuit which has meant the removal of four 90-degree corners towards the end of the lap.

The total number of corners has dropped from 22 to 19 with lap times around eight seconds faster.

That will add a new element of uncertainty -- team strategists will have less time to make calls on whether to pit for new tyres during the safety-car periods that frequent the Singapore race.

Wolff believes Mercedes may have their best chance to upset Red Bull on a track where straight-line speed is not so crucial but grid position is everything because of the difficulty in overtaking.

"Singapore is back to high downforce and coming towards our direction a little bit more," he said. 

"It will be important for us to maximise that opportunity when it comes."

dh/pst