Jack Miller kept his Moto3 title battle with Alex Marquez alive by taking second at Sepang while his rival was only fifth.
The result brings Marquez's lead down from 20 to 11 points with just the Valencia finale remaining.
The championship rivals made contact repeatedly in an extremely tense race in Malaysia, with Miller making sure Marquez was sent wide whenever the two came close through the corners.
Marquez - brother of MotoGP world champion Marc - put himself on the outside of Miller again as they fought for the lead going into Turn 1 on the last lap.
Although there was no touch this time, Marquez was edged wide enough to fall to fifth behind Miller's Ajo team-mate Danny Kent, which is where he would finish - prompting remonstrations with Kent on the slowing-down lap.
Miller then became embroiled in a battle with Marquez's Monlau team-mate Alex Rins and Efren Vazquez, with Vazquez snatching the win through the final turn.
The result means that if Miller wins at Valencia, he needs Marquez to be fourth or lower to claim the title.
Third place, from 17th on the grid, was not sufficient to keep Rins in contention.
LEADING RESULTS - 18 LAPS:
|2||Jack Miller||Red Bull KTM Ajo||KTM||0.213s|
|3||Alex Rins||Estrella Galicia 0,0||Honda||0.385s|
|4||Danny Kent||Red Bull Husqvarna Ajo||Husqvarna||0.803s|
|5||Alex Marquez||Estrella Galicia 0,0||Honda||0.831s|
|7||Niccolo Antonelli||Junior Team GO&FUN Moto3||KTM||1.916s|
|8||Jakub Kornfeil||Calvo Team||KTM||2.089s|
|9||Karel Hanika||Red Bull KTM Ajo||KTM||7.336s|
|10||Enea Bastianini||Junior Team GO&FUN Moto3||KTM||9.520s|
CHAMPIONSHIP STANDINGS AFTER 17 OF 18 ROUNDS: