Jorge Lorenzo was fastest in final practice at Sepang, ahead of the race that could see him crowned MotoGP world champion for the first time.
The Yamaha rider only needs ninth place in tomorrow's Malaysian Grand Prix to clinch the title, and he will go into qualifying in strong form after edging out Casey Stoner in this morning's session.
Stoner (Ducati) had been on top for the majority of the hour, but a late 2m01.949s lap from Lorenzo saw the Australian beaten by just 0.022 seconds.
Friday pacesetter Valentino Rossi completed the top three on the second Yamaha.
Honda's Andrea Dovizioso was fourth, but until the closing moments the fastest Honda had been Gresini rider Marco Simoncelli, who held third for a while and ended the session still in fifth.
Alvaro Bautista maintained his strong Friday form to take sixth for Suzuki - but his team-mate Loris Capirossi's participation in qualifying could be in doubt after a big crash for the Italian veteran at the start of practice.
Capirossi had a violent high-side at Turn 12 on his very first lap of the session, landing heavily. He struggled to get up and had to be taken away by stretcher.
Randy de Puniet was seventh for LCR Honda, with Tech 3 Yamaha duo Colin Edwards and Ben Spies sandwiching Aspar Ducati's Hector Barbera in eighth and 10th, and Nicky Hayden showing slightly better form than yesterday to take the second Ducati to 11th.
Pos Rider Team Time Gap 1. Jorge Lorenzo Yamaha 2m01.949s 2. Casey Stoner Ducati 2m01.971s + 0.022s 3. Valentino Rossi Yamaha 2m02.192s + 0.243s 4. Andrea Dovizioso Honda 2m02.311s + 0.362s 5. Marco Simoncelli Gresini Honda 2m02.543s + 0.594s 6. Alvaro Bautista Suzuki 2m02.617s + 0.668s 7. Randy de Puniet LCR Honda 2m02.638s + 0.689s 8. Colin Edwards Tech 3 Yamaha 2m02.774s + 0.825s 9. Hector Barbera Aspar Ducati 2m02.796s + 0.847s 10. Ben Spies Tech 3 Yamaha 2m02.818s + 0.869s 11. Nicky Hayden Ducati 2m02.849s + 0.900s 12. Aleix Espargaro Pramac Ducati 2m02.921s + 0.972s 13. Hiroshi Aoyama Interwetten Honda 2m03.069s + 1.120s 14. Marco Melandri Gresini Honda 2m03.456s + 1.507s 15. Mika Kallio Pramac Ducati 2m03.711s + 1.762s 16. Loris Capirossi Suzuki