MotoGP world champion Jorge Lorenzo was the class of the field on the opening day of Sepang pre-season test.
The Yamaha rider emerged more than a second faster than his nearest rival and team-mate Valentino Rossi during the hit-out at the Malaysian circuit.
The session represented the first opportunity that the entire field ran the new Michelin tyres and control electronics which have been introduced this year.
Lorenzo was the only man to dip under the 2:01s bracket when he posted a session best 2:00.684s effort early in the running.
Rossi improved throughout the day with the nine-time champion's best time just before rain curtailed the session in the final hour.
Factory Ducati rider Andrea Iannone was fifth as he debuted the manufacturer's 2016 machine in the afternoon. Team-mate Andrea Dovizioso running the 2015 bike was a lowly 13th.
The Italian manufacturer has confirmed that new development rider Casey Stoner will feature in the second day of the test today.
It will be the Australian's first official timed MotoGP session since Valencia in 2012.
Avintia Racing's Hector Barbera was an impressive sixth in front of Honda's Marc Marquez who was more than 1.5s shy of Lorenzo.
The former two-time champion believes he has plenty of work to do to adapt to the changes for 2016.
“After going the entire winter without getting on my bike, today we began the first pre-season test of 2016,” said Marquez.
“We still have a lot of work to do, as we have new electronics, a new engine and a few different engine specs to what we used in Valencia and Jerez back in November.
“In terms of setup, we made very few adjustments, because we were focused on the electronics and adapting it to my riding style.
“It's true that neither my place on the timesheet or lap time today are great, but this is going to be a long pre-season in which we will have to work hard on many different things.”
Pramac Racing's Scott Redding, Suzuki's Aleix Espargaro and LCR Honda's Cal Crutchlow completed the top 10.
Australia's Jack Miller was absent from the test as he continues to recover from a leg injury sustained in a training accident.
Result: MotoGP Sepang Test Day 1