The Ferrari driver arrived at Suzuka with a 29-point advantage over Red Bull’s Sebastian Vettel, but a first-corner crash and a consummate triumph for his rival narrowed the gap to just four points with five races left.
Alonso made contact with the front wing of Kimi Raikkonen’s Lotus as he edged to the outside on the run down to turn one, puncturing a rear tyre and sending the Ferrari into the gravel before coming to a halt in the middle of the track.
Vettel went on to cruise to a comfortable victory and on current form it is hard to see how Alonso can fend off the German’s push for a third-straight title given Red Bull’s edge in performance.
“This result has practically wiped out the advantage I had before, but if I’d been told at the start of the season that we would have been in this situation five races from the end, I’d have happily signed for it,” said Alonso.
“Now we start a sort of mini-championship, run over five grands prix. The aim will be to score at least one point more than all the others.” The next round in Korea is just a week away, a race Vettel won comfortably in 2011.
Although he is now the favourite to secure the crown in the eyes of many, Vettel chose to strike a cautious note.
“There are many races to go so today I don’t want to talk about the championship.”
McLaren’s Lewis Hamilton, after a weekend dominated by talk regarding his impending move to Mercedes, also closed the gap on Alonso with a fifth place finish.
Hamilton never recovered from taking a wrong turn on set-up ahead of qualifying and he cut a downbeat figure with his title challenge fading.
“I am quite realistic, I know my situation, but the Red Bulls are going to be hard to beat,” he said.
“I got some points but there is not much more I can be happy with.”