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.

However Rossi ran wide under braking to the end of the back straight on lap two, allowing both Repsols ahead. An identical mistake next time around saw Rossi run into the gravel and re-join down in eleventh.

Behind Rossi, Monster Yamaha Tech 3 team-mates Cal Crutchlow and Bradley Smith, plus Ducati team-mates Nicky Hayden and Andrea Dovizioso completed the top ten.

Yamaha test rider Katsuyuki Nakasuga, who claimed a shock podium in the damp at Valencia 2012, finished eleventh as a wild-card entry.

Forward's Colin Edwards was the top CRT rider in twelfth after Aspar's Aleix Espargaro - already confirmed as privateer class champion - appeared to bail-off his ART at the end of the back straight shortly after the halfway mark.

Sunday's race was only the third MotoGP track session of the weekend, with fog forcing the cancellation of all track activities until Saturday afternoon.

In the 2006 MotoGP title showdown, Nicky Hayden overturned Valentino Rossi's points lead at the Valencia finale.

Japanese MotoGP:
1. Jorge Lorenzo
2. Marc Marquez
3. Dani Pedrosa
4. Alvaro Bautista
5. Stefan Bradl
6. Valentino Rossi
7. Cal Crutchlow
8. Bradley Smith
9. Nicky Hayden
10. Andrea Dovizioso
11. Katsuyuki Nakasuga
12. Colin Edwards
13. Randy De Puniet
14.Andrea Iannone
15. Yonny Hernandez
16. Hector Barbera
17. Hiroshi Aoyama
18.Danilo Petrucci
19. Michael Laverty
20. Claudio Corti
21. Damian Cudlin
22. Bryan Staring
23. Aleix Espargaro
24. Luca Scassa
25. Lukas Pesek