Now or never for Vettel in F1 title fight

Time is running out on Ferrari's Sebastian Vettel in the F1 title showdown with Lewis Hamilton.

It's now or never for Ferrari's Sebastian Vettel in the F1 title showdown with Lewis Hamilton. (AAP)

It's now or never for Sebastian Vettel and his Ferrari team on Sunday at the Singapore Grand Prix in the Formula One title fight with Mercedes' Lewis Hamilton.

On no other of the seven remaining courses Ferrari are considered such big favourites over Mercedes as on the 5.065km Marina Bay street course where the drivers will race under floodlights.

Vettel certainly has fond memories of Singapore as he is a record four-time winner there, with last year's victor Hamilton on three top spots.

But he and the Scuderia must deliver after the home race meltdown in Monza where Vettel and teammate Kimi Raikkonen locked out the front row on the grid but Hamilton then won - after first-lap contact with Vettel who had to fight from behind and settle for fourth.

Despite Raikkonen's runner-up finish the outcome was a massive disappointment for Ferrari while at the same time it boosted Mercedes' morale.

Hamilton is now 30 points clear of Vettel which is more than the 25 points for a race win but the German is far from throwing in the towel.

"There are many points to win back now in the championship, but we still have time to improve and we have the margin to recover," he said.

"I know what has to be done. I am concentrating on Singapore. I like the place."

Mercedes motorsport chief Toto Wolff is meanwhile cautiously optimistic that his team of Hamilton and Valtteri Bottas can get the better of the Ferraris.

"On paper, the track should favour the Ferraris, but the championship fight is so close that predictions are almost meaningless," he said.

"Last year, we started the race from the third row - and came home with a win and a third place."

To spice things up, Red Bull with Max Verstappen and Australian Daniel Ricciardo also like their chances on the twisting, bumpy Singapore course.

"I've had four podiums and three second places in a row there, so it's about time I win the damn thing," Ricciardo said.