Sebastian Vettel remains cautious on his hopes of winning a third straight Formula One world title, despite moving to within four points of championship leader Fernando Alonso with victory at the Japanese Grand Prix.

The Red Bull was the class of the field at Suzuka and Vettel took full advantage, completing the clean sweep of pole position, fastest lap and race win. But the German's hopes received an added boost when Alonso was eliminated at the first corner of the race.

But, despite taking his third win of the season and second in succession, Vettel does not consider himself favourite, and he said: "I'm very careful. I think we had a long journey so far, and it's been a tough year. Still there are many races to go so I don't want to talk about the championship."

Alonso had started sixth on the grid, as Ferrari again struggled for one-lap pace in qualifying, and paid the price when he made contact with Kimi Raikkonen's front wing on the run down to turn one.

The front-wing endplate of the Lotus gave Alonso a puncture, which saw his Ferrari run into the gravel before eventually coming to a halt in the middle of the track.

It was the second time Alonso had failed to get further than the first corner in four races, after being eliminated by Romain Grosjean in Belgium. The Frenchman got himself involved in another first-lap incident here by ramming Mark Webber at turn two.

On current form it is difficult to see Alonso and Ferrari being able to fend of Vettel and Red Bull, but Vettel remains cautious and added: "I know I finished in front of everyone. I won the race, so I know that I scored more points than anybody else here but you don't know what happens next weekend.

"I think we have a very tough remainder of the season with a very new calendar for all of us, with a lot of back-to-back races.

"Basically next week Korea, then two races, one in India and Abu Dhabi, and then obviously America and Sao Paulo.

"I think there's still a long way to go and, as I said, we have to focus on every single race and try to do our best and then we will see whether it's good enough."