New factory Ducati MotoGP rider Marc Marquez took pole position in his first qualifying in Ducati red for the 2025 season opener in Thailand.
Team-mate Pecco Bagnaia fought his way through Q1 but had no answer to Marquez in the pole shoot-out, with the latter easing to pole despite a relatively messy session.
Marquez fired in a 1m28.782s in the early going of Q2 - under a tenth of a second off Bagnaia's lap record from last year - and then had a difficult run on his second rear tyre.
He made an error on his first push, then caught yellow flags for Turn 3 crashes - first for Aprilia's Marco Bezzecchi, then for Honda's Joan Mir - on his next two attempts.
Still, he tried for a last-second effort - and, while off his own benchmark, was anyway still 0.001s quicker than Bagnaia's best from a few minutes prior.
Bagnaia still salvaged a front row - a win given his troubled Friday - but Gresini Ducati rider Alex Marquez pipped him, too, making it a Marquez 1-2 at the front of the grid.
Jack Miller timed his second run to perfection to catch a tow from his good friend and former team-mate Bagnaia, so will start a superb fourth on his Pramac Yamaha debut.
Trackhouse Aprilia debutant Ai Ogura was a mesmerising third after the initial runs, and though he couldn't match that time after returning to the track he still ended up fifth.
VR46 Ducati rider Franco Morbidelli should be completing row two - and will do so on Saturday - but will instead complete row three for the main event, due to his penalty for having baulked Bagnaia on Friday.
Morbidelli was sixth-fastest but moves behind Pedro Acosta (the sole KTM representative in Q2), Ogura's team-mate Raul Fernandez and Bezzecchi on the Sunday grid.
Fabio Quartararo (Yamaha), Mir and Johann Zarco (LCR Honda) completed a Q2 covered by just 0.827s - and that's with Zarco being two tenths adrift at the back.
Thai GP grid
1 M Marquez 2 A Marquez 3 Bagnaia
4 Miller 5 Ogura 6 Acosta
7 Fernandez 8 Bezzecchi 9 Morbidelli
10 Quartararo 11 Mir 12 Zarco
13 Di Giannantonio 14 Binder 15 Aldeguer
16 Marini 17 Oliveira 18 Vinales
19 Rins 20 Bastianini 21 Savadori
22 Chantra
Fabio Di Giannantonio, who suffered badly on Friday with not just pain in his healing collarbone but shoulder pain, too, found a reasonable step in qualifying but came up half a tenth short of advancing into Q2.
Rookie Fermin Aldeguer was the only other Ducati to miss out, but did at least move up to 15th on the grid for his debut with his final lap.
Brad Binder slotted in between them, never really too much of a threat to make Q2 - as was also the case for the two Tech3 KTM newcomers Maverick Vinales and Enea Bastianini.
Everyone but Aprilia stand-in Lorenzo Savadori was within a second of Bagnaia's benchmark in Q1 - though rookie Somkiat Chantra (LCR Honda) will drop behind Savadori on the Sunday grid due to his own three-place penalty for impeding.
