Pramac Racing's Jorge Martin won the sprint at the season-ending Valencia Grand Prix to cut Francesco Bagnaia's world championship lead and set up an epic showdown in Sunday's finale.

Martin, who started sixth on the grid on on Saturday, put in a battling display for his ninth sprint win of the season as Ducati's Bagnaia crossed the line in fifth place at the Circuit Ricardo Tormo.

Australia's Jack Miller finished in 12th place in the spring for Red Bull KTM but will start the final race of the season fourth on the grid.

As he has done on several occasions this season, Martin shot off the line and moved up from sixth to third in the matter of seconds, before riding on the coat-tails of Brad Binder to surge past Bagnaia towards the end of the first lap.

Martin made his play for the win in the eighth lap, picking off pole-sitter Maverick Vinales with a burst of speed on the straight and then taking advantage of a mistake from Binder as he squeezed into the lead when the South African ran wide.

KTM's Binder finished second, ahead of Honda's six-times MotoGP champion Marc Marquez. Aprilia's Vinales ended in fourth.

Bagnaia, stranded in fifth place after the first lap, was unable to make up ground on the leading four but did well to hold off challenges from Yamaha's Fabio Quartararo and Gresini Racing's Fabio Di Giannantonio.

The Italian, who has six race victories this season, is now on 442 points while Martin has 428.