Red Bull Racing's Sebastian Vettel collected his ninth win of the season at Suzuka, but was forced to work hard for the victory thanks to feisty performances from his team-mate Mark Webber and Lotus driver Romain Grosjean.
Maximum points propelled the victorious German to within touching distance of a fourth consecutive world championship, although a solid fourth place for Ferrari's Fernando Alonso kept the points fight mathematically alive for another race.
On Saturday Webber had pipped his Red Bull team-mate Sebastian Vettel to pole position, but Grosjean, who qualified fourth, sliced past both to lead into the first corner.
Lewis Hamilton's race was effectively over on the sprint to the first corner. He made an excellent getaway and squeezed into a narrowing gap between Webber and Vettel, but the slightest of contact with the Red Bull's front wing punctured Hamilton's right-rear tyre. The Briton limped back to the pits for a replacement tyre, but later retired with handling issues.
Grosjean coolly controlled the race through the first round of pit stops, but he was unable to pull more than a couple of seconds clear of Webber, with Vettel maintaining a watching brief in third position.
Webber closed to within one second of Grosjean as the race approached halfway, but peeled into the pits for more new tyres before he had chance to attack. It was a comparatively early stop that put him onto a three-stop plan, but it soon became clear tha the Red Bull team had put its cars on split strategies; third-placed Vettel had conserved his second set of tyres well and was opting for just two stops. He remained out on track and began to take chunks out of the Frenchman's lead.
Grosjean made his second stop on lap 30, which promoted Vettel to the lead. Meanwhile, Webber had been setting quick lap times and leapfrogged Grosjean during the pit stops.
Vettel assumed the lead and remained out on track on his hard set of tyres for much longer than his rivals. His plan was to pull enough of a lead over Grosjean to enable him to make his second tyre stop and emerge still ahead of the Lotus racer. He needed more than 20 seconds to pull it off, but as Vettel stretched his worn tyres as far as he dared, it looked to have been a close-run thing.
Indeed, when Vettel finally changed his tyres at the end of lap 37, Grosjean moved back ahead. Vettel, armed with tyres that were eight laps fresher, was now the pursuer and went on the attack, slashing the two-second gap to his rival.
On lap 41 Vettel used the drag reduction system to storm past Grosjean on the start-finish straight and immediately pulled away.
Both men were still 15sec behind Webber, who was also setting some fast laps up at the head of the field. He peeled in at the end of lap 42 and put on a set of soft tyres, resuming in third place behind Vettel and Grosjean and immediately setting about chasing his rivals.
He reeled in Grosjean, and tried to slip past on the main straight on lap 47, but the Lotus racer defended stoutly. As they fought over the position, it gave Vettel the opportunity to eke out a few more seconds up at the front of the field. It was a crucial moment; if Webber had been able to quickly vault Grosjean, he might have been able to catch his team-mate and attack for the lead.
With three laps to go, Grosjean and Webber came up to lap a huge glut of back markers who were furiously fighting for position. Webber got a great run as they exited the chicane with two laps to go and squeezed between a defending Grosjean and the pit wall to seize the position. He sped clear, but any prospect of catching his team-mate had been extinguished.