Wet Assen winner Jack Miller led a damp free practice 2 for the Malaysian MotoGP courtesy of a final lap attack.
The Marc VDS Honda rider, 16th in the morning session, joined the likes of Cal Crutchlow and Scott Redding in making a late switch to slicks on the drying track.
Crutchlow was first to move to the top, ahead of Avintia Ducati's Loris Baz on intermediates, with Miller lapping 0.399s quicker moments later.
The Australian's lap time of 2m 8.872s was over seven-seconds slower than the almost dry morning pace of world champion Marc Marquez. However the Repsol Honda star was absent this afternoon due to due to a gastroenteritis, having spoken of an illness on Thursday.
Hector Barbera (Avintia Ducati), Bradley Smith (Tech 3 Yamaha) also beat Baz's best at the end of the session, with Scott Redding (Pramac Ducati), Andrea Dovizioso (Ducati), Stefan Bradl (Aprilia), Tito Rabat (Marc VDS Honda) and Dani Pedrosa's replacement Hiroshi Aoyama (Repsol Honda) completing the top ten.
But like Miller, Crutchlow (13th) and Dovizioso (15th) are currently outside the top ten on combined practice times, meaning they will have to hope for dry conditions on Saturday morning to have a chance of avoiding Qualifying 1.
During the session Pedrosa - currently recovering from collarbone, leg and foot injuries sustained in Japan - tweeted to deny rumours that he is considering retirement.
The Sepang International Circuit has been resurfaced and nine track sections modified in terms of camber, kerbing and bumps since the February test.
Lap times are predicted to be around two-seconds faster in clean and fully dry conditions, with all the changes making the track faster with the exception of negative camber at the final corner.
Andrea Iannone, making his return from back injuries, joined Marquez in missing the afternoon session.
1. Jack Miller
2. Cal Crutchlow
3. Hector Barbera
4. Bradley Smith
5. Loris Baz
6. Scott Redding
7. Andrea Dovizioso
8. Stefan Bradl
9. Tito Rabat
10. Hiroshi Aoyama
11. Alvaro Bautista
12. Eugene Laverty
13. Valentino Rossi
14. Yonny Hernandez
15. Pol Espargaro
16. Jorge Lorenzo
17. Maverick Viñales
18. Danilo Petrucci
19. Aleix Espargaro
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