The MotoGP title fight has taken a massive twist after rookie Marc Marquez was black flagged from the Australian Grand Prix, won by nearest rival Jorge Lorenzo.

Phillip Island was the first ever MotoGP race to feature mandatory pit stops, due to concerns over overheating tyres on the new asphalt.

But Marquez - who had been battling Lorenzo and Dani Pedrosa for victory - failed to change to his spare bike within the ten lap limit.

Lorenzo, Marquez and Pedrosa were covered by just a few tenths when Pedrosa peeled into the pits at the end of lap 9 of a reduced 19 laps. Lorenzo then pitted a lap later - but Marquez did not.

Instead the rookie pitted at the end of lap 11 and was later disqualified as a result. Repsol Honda said it appears to have been a 'team mistake'.

Marquez had left the pits on his second bike and was promptly hit by race leader Lorenzo as their lines crossed at the ultra-fast first turn. Something on Marquez's bike or gloves fell off in the contact.

Timing screens then declared that second place Pedrosa needed to drop one position for touching a pit lane filter line. Pedrosa duly allowed Marquez past, just before a dejected Marquez was officially issued with his black flag.

Marquez, who had the chance to win the title today, has instead seen his championship lead cut from 43 to 18 points, with two rounds remaining.

With spots of rain falling, Lorenzo won his sixth race of the season by 6.9s from Pedrosa. Lorenzo's Factory Yamaha team-mate Valentino Rossi emerging on top of a thrilling photo finish for third with Cal Crutchlow (Tech 3 Yamaha) and Alvaro Bautista (Gresini Honda).

Bradley Smith, Nicky Hayden, Andrea Iannone, Andrea Dovizioso and Randy de Puniet completed the top ten, while eleventh place for Aleix Espargaro confirmed the Aspar rider as the CRT class champion.

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