MotoGP world champion Marc Marquez was fastest across Friday's two practice sessions for the Malaysian Grand Prix, despite missing FP2 with illness.
Marquez, who claimed a third title in Japan but crashed out in the previous race in Australia, went fastest in FP1 on a track drying after overnight rain with a time of two minutes and 1.210 seconds.
The Repsol Honda rider did not return for the second session, though, instead heading to the medical centre for gastroenteritis treatment.
However, Marquez's time remained the best following the conclusion of the FP2 as a heavy downpour between sessions saw lap times rapidly drop off - Jack Miller (Marc VDS) quickest at two minutes and 8.872secs
Ahead of his move to Movistar Yamaha, Maverick Vinales has been performing excellently in the closing stages of his Suzuki Ecstar career.
After successive podiums in Japan and Australia, Vinales came in just 0.268secs behind Marquez and Scott Redding (Pramac) was third quickest.
Andrea Iannone has not raced for Ducati since sustaining a fractured vertebra at Silverstone in September but his form seemed unhindered as he was fourth fastest at Sepang.
Valentino Rossi was behind his fellow Italian in fifth, while Movistar Yamaha team-mate Jorge Lorenzo was back in 10th.