Sebastian Vettel remains sure he can challenge Lewis Hamilton for a fifth Formula 1 title despite seeing the gap grow to 28 points after failing to finish at the Singapore Grand Prix.

The German appeared at fault for triggering an incident between himself, Max Verstappen and teammate Kimi Raikkonen at the start, as the three cars pinched together, with Sebastian moving across, on the run to the first corner.

A spin into the wall on the run to Turn 5 would then guarantee his first retirement of 2017 but, commenting on the incident on the return to the paddock, the man who started from pole defended his actions insisting he was unaware of the presence of two cars on his inside. 

"I don't know, I had an average start," said Vettel. "I went to the left, tried to fend off Max then the next thing there was a bump on the side, saw Kimi's car, not sure what happened.

"Then I spun after Turn 3 but I think there was damage on the car already and it didn't matter, [the car was] broken, massively bent, I lost water pressure and had to stop anyway."

Heading into the weekend, it was thought a strong result was imperative for Vettel and his championship aspirations with Ferrari likely to have the advantage on Mercedes and Red Bull competitive too. Instead, the margin between the two leaders is now the largest it has been all year, with Hamilton now over a race win clear of the 30-year-old. 

However, talking as the race continued, Vettel is sure there is still time for luck to swing in his favour. 

"It's a long race, we are on the wrong side of the track so that doesn't help, but we've got races to go, nothing we can do now, for sure it's bitter, but it's done," he said.

“It is what it is and we move on. It doesn’t change much. Obviously, we are not in the race, that’s a pity, we can’t show the pace that we have but I am sure there will be more opportunities.”