Vettel hitches a ride back to the pits with Sauber driver Pascal Wehrlein after Lance Stroll driove into the back of his Ferrari. Picture: Thomas Lam / AP

Sepang, Malaysia - Sebastian Vettel's Formula One title bid could suffer a further setback after a bizarre post-race incident at the Malaysian Grand Prix on Sunday.

Vettel, now 34 points behind Mercedes' championship leader Lewis Hamilton with five races remaining, was in a collision with Lance Stroll's Williams on the slowing-down lap.

"Stroll just drove into me. I mean, seriously." he exclaimed. The impact smashed the rear left of the Ferrari with potential damage to the gearbox, which would incur a five-place penalty if it needs to be replaced for the Japanese Grand Prix next weekend.

"I hope not because, as I said, it was completely unnecessary," said the four times world champion after hitching a ride on Pascal Wehrlein's Sauber back to the pits.

Vettel had started in last place after a power unit problem in qualifying but worked his way up to fourth in a performance that emphasised the car's pace and what might have been; Hamilton was second.

Confronting problems

It could have been even worse for Vettel, however, with team-mate Kimi Raikkonen failing to start after a loss of power on the way to the grid.

Team principal Maurizio Arrivabene commented: "It all added up to our hardest race of the year, as we had to confront problems that we will now analyse in depth." 

"I think it’s enough now of cars turning one way or the other and ending having a shunt," Vettel said, suggesting 18-year-old Stroll had not been looking where he was going. "That was a bizarre one, for sure."

But the Canadian sounded baffled by that; he said he had been driving slowly back to pit lane, steering a normal line and going through switch changes.

"It was just a very strange incident," said the eighth-placed finisher. "Obviously the race wasn’t going on so it wasn’t intentional for either of us," 

The stewards decided to take no further action.