Francesco Bagnaia won the Thai MotoGP on Sunday to close the gap on championship leader Jorge Martin with two race weekends left, with the Spaniard second in tricky wet conditions.
Martin's lead over defending champion Bagnaia of Italy was cut from 22 points to 17, ahead of another chapter in their title tussle at Sepang in Malaysia next week.
Pedro Acosta was third at Buriramm while South Africa's Brad Binder finished sixth.
Pramac Ducati's Martin began the race on the front row in third and made a lightning start to grab the lead from his pole-sitting rival.
But the 26-year-old did not stay there long, running wide to fall to third as Bagnaia took the lead with six-time MotoGP world champion Marc Marquez in hot pursuit.
