Red Bull team boss Christian Horner struggled to watch Sebastian Vettel's closing laps during Korean Gran Prix victory

Sebastian Vettel in action in Korea (GETTY IMAGES)

Red Bull team boss Christian Horner admitted there were moments when he was almost too scared to watch after Sebastian Vettel overcame tyre degradation concerns to win in South Korea and take over the lead of the World Championship.

Tyre management had been the watchwords among teams and drivers over the course of the weekend, but Red Bull appeared in little danger with Vettel and team-mate Mark Webber running at the head of the field.

But during the closing stages Vettel's race engineer Guillaume 'Rocky' Rocquelin could be heard over the radio demanding his driver ease off in certain sections of the track in order to lessen the strain, particularly on his right front tyre.

Vettel's desire to set the fastest lap during a race is well known, and that left Horner even more concerned that the German's desire to push for a quick lap could wring the last bit of life from his Pirelli rubber.

Horner said: "It was quite a long final stint, it was 22 or 23 laps, which we knew would be right on the limit.

"So it was about making sure we did not punish the tyres too much and making sure we had enough to get to the finish.

"That is why I said to Rocky 'make sure you are all over Sebastian because we don't need any fastest laps and then have Mark trying respond one lap from the end'.

"Knowing how much we had stretched the tyres was a concern, other teams must have had the same issue, and then every time the TV was bringing up a slow-motion replay of bits of an inner edge flying off (the tyre).

"I decided I could not look at those any more from about half distance, I focused on the data instead."

Vettel managed to make it to the flag without incident, and went six points clear of Fernando Alonso at the top of the standings as he looks to become just the third driver to win three consecutive titles.

Despite Red Bull's supreme performances in Japan and Korea, Horner insists nothing is being taken for granted.

He said: "There is a long way to go, Sebastian is six points in the lead with four to go but his main opponent was only one place away from him on the podium, so we are not thinking about championships yet."

PA