MotoGP will have its first title showdown since 2006 after Jorge Lorenzo took victory in Sunday's Japanese Grand Prix at Motegi.
Lorenzo weathered constant pressure from championship leader Marc Marquez and team-mate Dani Pedrosa for the majority of the race, before breaking the challenge of the Honda riders.
Yamaha's reigning double champion seized his seventh victory of the season by 3.188s over Marquez, with Pedrosa 4.592s adrift in third.
The result means that Marquez has seen his championship lead cut from 18 to 13 points over Lorenzo heading into the Valencia finale on November 8-10, while Pedrosa is now mathematically out of title contention.
Marquez - black flagged during his first title chance last weekend in Australia - fell heavily in Sunday morning practice, receiving treatment for 'mild neck and back pain' prior to the race, which he started alongside pole sitter Lorenzo.
The leading trio - Lorenzo, Marquez and Pedrosa - surged ten seconds clear of the field by the halfway stage of the 24 laps, before Pedrosa began to fade.
That left a straight Lorenzo-Marquez duel, with Lorenzo remaining wheel perfect as he pounded out fastest race laps at the Honda-owned circuit. Marquez meanwhile began making small mistakes under braking and lost touch with Lorenzo with seven laps to go.
Lorenzo - who ran the softer rear tyre, rather than the harder option on the Hondas - was later held up by a lapped Damian Cudlin, but it wasn't enough to put Marquez back within reach.
Satellite Honda riders Alvaro Bautista and Stefan Bradl claimed fourth and fifth places, ahead of Valentino Rossi. Rossi had rocketed from fifth to second at turn one, making him ideally placed to hold up the Hondas and allow team-mate Lorenzo to escape.