Handling on Vettel's Ferrari F1 car became 'violent' in US GP

The German's SF16-H routinely lost downforce during what would have been his final stint at Austin, getting out of shape through the high-speed esses in the opening sector.

Ferrari pitted Vettel again with four laps to go, as a precaution given his track position in an isolated fourth place, cleaning the rear wing and fitting super-soft tyres.

Team boss Maurizio Arrivabene said there was rubber on the rear wing, which was causing it to stall.

"It was quite violent," said Vettel. "We had some issues, especially at the end of the race.

"It is quite surprising if you lose downforce very suddenly.

"It's not like someone is knocking one or two seconds before, and tells you you're about to lose the car so I was quite lucky in that instance to be able to save it.

"It was quite a big snap.

"We were travelling at quite high speeds but I was able to save the car.

"I had a couple of moments in the race and after that, I slowed down a bit to take it easy as we didn't have anywhere to go.

"We were 10 seconds behind Daniel [Ricciardo] and there was nothing going on behind."

Vettel believes the virtual safety car, triggered by Max Verstappen's Red Bull stopping on track, cost him the chance of a podium finish.

He tried a different strategy to his direct competitors, running a long first stint on the super-softs and leading briefly.

Vettel switched to the softs for his second stint and then stopped for the mediums 15 laps later to cover Verstappen, only for the VSC to appear a few laps later.

"We stayed out longer with people in front of us pitting sooner, so it was a chance for us to try something different," he said.

"Then we pitted early to go on the medium tyre to keep track position to Max but a lap later or two laps later the VSC came out, so that was not ideal.

"Otherwise, we could have had a crack at the podium.

"All in all, the race was a lot better than qualifying in terms of competitiveness, but it is a shame we didn't get both cars to the chequered flag."

Vettel's Ferrari team-mate Kimi Raikkonen retired, when running fourth, after the team failed to secure his right-rear tyre properly during his third pitstop.