Yeongam: Sebastian Vettel survived a late tyre scare to move back to the top of the Formula One drivers' championship with a dominant victory in Korea, as McLaren's title hopes disintegrated.
The Red Bull driver got the jump on teammate Mark Webber from second on the grid and was able to ease away to his third win in a row and go six points clear of Fernando Alonso, despite concerns his right-front tyre would wear out in the closing laps.
Webber was a solid second as Red Bull became the first team to secure a one-two finish in 2012, with Alonso getting the maximum out of his Ferrari with third place.
But Lewis Hamilton could only finish 10th after suffering with tyre degradation and fell 62 points behind Vettel with just 100 points up for grabs from the final four races. Teammate Jenson Button was a first-lap retirement and is 84 points adrift of the German.
Much of the pre-race speculation had centred around whether Webber would be willing to move over for Vettel to help his teammate's championship chances.
As it turned out any concerns proved unnecessary as Vettel got the better start from the dirty side of the grid and went up the inside of Webber into turn one to take a lead he never relinquished.
Behind the two Red Bulls the Ferraris made good starts as Alonso got by Hamilton and Felipe Massa made a move on Kimi Raikkonen for sixth. But behind them Button, who had started 11th, and Nico Rosberg were already out of the race.
The pair were clouted by the wayward Sauber of Suzuka hero Kamui Kobayashi at turn three and went no further, the Japanese driver serving a drive-through penalty before being forced to park up in the garage.
Vettel quickly began to eke out a lead over Webber as the top six held position through the first-round of stops. But this proved to be the start of Hamilton's woes.
The Briton had failed to do a meaningful long run during practice and soon found his tyres to be wearing at an alarming rate, and Massa breezed past him on the run to turn three before he was forced to pit for a second time several laps earlier than his rivals.
It would have ramifications later on.
Vettel's was comfortably managing the gap back to Webber, but had tyre struggles of his own during the latter stages of his second stint, which meant his team-mate got back within 5.3 seconds.
But once he pitted Vettel quickly reasserted his authority with a lap 1.5 seconds better than his team-mate and the advantage was soon back up to 8.5 seconds.
"The start was very important. We started from the dirty side," said Vettel.
"I had a very good launch and could see that Mark was struggling a little bit. I was able to get side by side and then had the inside into turn one.
"It was a perfect start for myself," added the German, who spent the closing laps fretting about the tyres and making sure they held up.
Meanwhile Hamilton's tyre woes had returned and it became apparent he would need to make an extra stop before the end. He desperately tried to keep Romain Grosjean and Nico Hulkenberg at bay, but eventually had to give way to the Force India as the German pounced around the outside at turn four, after Hamilton had run Grosjean out of road at turn three.
At Ferrari, Massa's excellent pace prompted a request for him to slow up in order to give team-mate Alonso some breathing space as he kept pace with the third-placed Spaniard.
Hamilton pitted again on lap 42 for the super-soft tyre and resumed down in 10th place.
It was at this point that Vettel's cruise to victory was thrown into doubt. He was advised to cool his pace with eight laps to go as the drivers struggled with heavy wear on their right-front tyres.
A further warning was issued to the German with five laps to go, while Hamilton's woes were compounded as he picked up a loose strip of AstroTurf under his McLaren which slowed his pace.
Vettel continued to receive increasingly concerned messages from race engineer Guillaume 'Rocky' Rocquelin, but ultimately came through to take the win by 6.8 seconds from Webber and close in on becoming just the third man to win three straight titles. Juan Manuel Fangio and Michael Schumacher are the others.
Alonso was a solid third for Ferrari as Massa underlined his recent improvement with fourth to allow the Italian team to move above McLaren into second in the constructors' championship.
Raikkonen was fifth ahead of Hulkenberg, Grosjean and the Toro Rosso pair of Jean-Eric Vergne and Daniel Ricciardo.
Hamilton salvaged a point for 10th, but will know his chances of leaving McLaren for Mercedes as a world champion are all but over.
Related report, results: Page 17