Gresini’s Sepang test leader Alex Marquez remained top of the timesheets on day one, when brother and reigning champion Marc Marquez battled sickness and two early crashes on his way to second place.
Meanwhile, Ducati Lenovo team-mate Francesco Bagnaia was the best of a handful of riders to try a Sprint simulation - with most of the field expected to show their cards with race runs on the final day, ahead of next weekend’s season opener.
Former world champion Jorge Martin briefly topped the timesheets for Aprilia on his 2026 debut, after missing Sepang, but it was team-mate Marco Bezzecchi who eventually finished the day as the top RS-GP rider in fourth.
Johann Zarco emerged as the top Honda rider in fifth, with Maverick Vinales the leading KTM in eighth after Pedro Acosta - like Bagnaia - chose to focus on a long run.
Jack Miller was the leading Yamaha V4 rider in 17th, with Fabio Quartararo struggling to contain his frustration on the way to 18th.
Tuesday is the last chance for riders and teams to gain track data before deciding on their start-of-season aero-package homologation.
Testing is again split into two sessions, with practice starts after each, but Sunday’s schedule starts half-an-hour earlier, at 9:30am and finishes at 5:30pm (instead of 6pm).
Jorge Martin moves up to fifth, just 0.284s behind test leader Bagnaia.
The top ten is now: Bagnaia, Bezzecchi, Acosta, Morbidelli, Martin, Ogura, Fernandez, Marini, Vinales, Alex Marquez.
Marc Marquez is only 17th, having done 13 laps, without trying for a time attack.
Francesco Bagnaia goes fastest on his 12th lap of the day with a 1m 28.883s, that's just a fraction behind Marc Marquez's best at last year's test and only 0.183s from Bagnaia's own all-time official lap record.
Francesco Bagnaia puts his factory Ducati into third, behind the Aprilia of Marco Bezzecchi and KTM of Pedro Acosta.
All three are under Alex Marquez's best day one time.
The Buriram paddock is awash with rumours that Bagnaia has agreed to join Bezzecchi at Aprilia for 2027.
Pedro Acosta is now just 0.069s from test leader Marco Bezzecchi.
All 22 riders have now been on track.
Marco Bezzecchi is the first rider to break into the 1m 28s this year. It's now also an all Aprilia top three, with Ai Ogura behind Bezzecchi and Raul Fernandez. Alex Marquez is the best Ducati in fourth, with brother Marc only 11th. The fourth Aprilia of Jorge Martin is seventh.
Aprilia riders Marco Bezzecchi and Raul Fernandez have become the first riders of the day into the 1m 29s.... Bezzecchi is just 0.192s away from a '28.
Rookies Toprak Razgatlioglu and Diogo Moreira, plus Pramac's Jack Miller, are now the only riders yet to start testing on the final day.
Reigning MotoGP champion Marc Marquez, second to brother Alex on day one despite sickness and two early crashes, has now joined the action.
The top ten after 20mins of testing:
Aprilia's Jorge Martin climbs into second place on his third lap of the day, splitting Morbidelli and di Giannantonio.
Fabio di Giannantonio has suffered a technical issue on his GP26 Ducati and has gone "back to pit".
Franco Morbidelli is currently leading VR46 team-mate Fabio di Giannantonio at the top of the timesheets with a 1m 30.148s. Then it's the KTMs of Maverick Vinales, Pedro Acosta and Brad Binder.
The green lights are on and testing is underway. Pedro Acosta, Maverick Vinales, Marco Bezzecchi, Fabio Quartararo, Franco Morbidelli, Raul Fernandez, Brad Binder, Alex Rins, Francesco Bagnaia and Ai Ogura head straight out on track.
The lap time to beat today is Alex Marquez's day one best of 1m 29.262s. However, most riders are also planning race simulations to prepare for this weekend's Thai MotoGP.
Good morning from Buriram, where the final day of 2026 MotoGP pre-season testing is about to start, at 9:30am local time, which is 30 minutes earlier than day one.