Marc Marquez took his 50th career MotoGP pole position after pipping Valentino Rossi to top spot in qualifying ahead of the inaugural Thailand Grand Prix by just 0.011 seconds.
A crash at the end of FP3 left Marquez in Q1 for the first time since Barcelona, though he eased through the first session to claim his fifth pole of the 2018 campaign and the first rider to take top spot in qualifying having come through Q1.
Yamaha's Maverick Vinales set the early pace at a 1:30.871s, though this was quickly eclipsed by Q1 pacesetter Marquez with a 1:30.528s, while Pramac's Danilo Petrucci slotted into second.
Fastest throughout practice, Dovizioso – who is the sole factory Ducati runner after teammate Jorge Lorenzo withdrew ahead of FP3 due to injury – emerged as Marquez's main threat with his opening gambit, putting his GP18 into second and missing out by just 0.063s.
Marquez responded, however, with a 1:30.356s to go over two tenths clear of the Italian with half the session still remaining.
With two minutes left on the clock, Rossi guided his Yamaha to the top of the timesheets with a 1:30.099s, though was deposed just 40 seconds later by Marquez, who fired in a 1:30.088s.
Rossi did put the Honda rider under pressure on his final lap, but just missed out on improving and remained second for his first front row since Brno.
Dovizioso also looked set to upset Marquez late on, but dropped too much time through the final section of the circuit and could only complete the front row with a 1:30.227s.
Rossi's Yamaha stablemate Vinales heads row two, missing third by just 0.001s, while Cal Crutchlow [LCR] headed Suzuki's Andrea Iannone to complete the top six.
Dani Pedrosa will start from seventh on the sister Repsol Honda, with Tech3's Johann Zarco and the Pramac pair of Petrucci and Jack Miller rounding out the top 10 ahead of Alex Rins [Suzuki] and Alvaro Bautista [Nieto].
Franco Morbidelli made himself a contender for a Q2 progression spot throughout the first qualifying segment, and the Marc VDS rider moved into second with a 1:30.923s on his last lap.
However, Rins' final lap shuffled Morbidelli back to third in the session by just 0.002s. The Italian will start 13th, with Takaaki Nakagami only 0.070s outside of a Q2 place in 14th.
Bradley Smith was top KTM runner in 15th with a 1:31.207s and did look like a Q2 threat late on, but lost time trying to pass Tech3's Hafizh Syahrin [18th] in the tighter middle section of the track.
Avintia stand-in Jordi Torres used his prior Buriram track knowledge to qualify his two-year-old Ducati 21st on the grid and just two tenths from his more experienced teammate Xavier Simeon on the GP17 in 20th.
