Valtteri Bottas swept to victory in Sunday’s Japanese Grand Prix as Mercedes clinched the Formula One constructors’ championship and guaranteed themselves an unprecedented sixth consecutive title double.

The Finn crossed the line 11.3 seconds ahead of Ferrari’s Sebastian Vettel, who made a hesitant start from pole position and had to fend off a charging Lewis Hamilton in the closing laps.

The result moved Mercedes 177 points clear of Ferrari, allowing them to wrap up a record-equalling sixth consecutive constructors’ crown, with a maximum 176 points from four races still to be won.

It also assured Mercedes of the drivers’ title with only Bottas now capable of challenging five-times world champion Hamilton, whose lead narrowed to 64 points.

Mercedes have now equalled Ferrari’s record six constructors’ titles in a row between 1999-2004. The Italian team won five successive drivers’ crowns with Michael Schumacher from 2000-04.

“Starting third is never easy here but there’s no point giving up,” said Bottas after his third win of the season and first since the Azerbaijan Grand Prix in April.

“I had a really nice car and Sebastian had an issue, so it was good to get the lead. Really proud of the team, a sixth title in a row is so impressive.”

Ferrari looked like they might delay the title celebrations after locking out the front row in a qualifying session held on Sunday morning, after being postponed from its traditional Saturday slot due to Typhoon Hagibis.

But both Vettel and team mate Charles Leclerc ran into trouble at the start.

Vettel launched off his grid spot a fraction too soon and slammed on the brakes before moving again. He was investigated for a false start but let off without a sanction because his car had not crossed the line.

The momentary hesitation was enough to allow Bottas to sweep around the outside and into the lead.

Leclerc collided with Max Verstappen as the Dutchman tried to pass around the outside, damaging the Ferrari and pushing the Red Bull, which later retired, into a spin.

The Monegasque nevertheless carried on, crucially holding up Hamilton as his car shed bodywork in a shower of debris before eventually pitting for repairs at the end of the third lap.

Leclerc, 21 and winner of two of the last five races, crossed the line sixth but dropped to seventh behind Renault’s Daniel Ricciardo after being slapped with two post-race time penalties.

He collected a five-second penalty for the Verstappen incident and a further 10 seconds for continuing to drive a car deemed to be in an unsafe condition.

Ferrari were also fined 25,000 euros ($27,600) for the latter offence while Leclerc was given two penalty points on his superlicence.

Ricciardo and 10th-placed team mate Nico Hulkenberg could still drop back, however, with Racing Point lodging a protest against the French manufacturer for an alleged brake bias infringement.