Marc Marquez prevailed in an epic duel with Andrea Dovizioso to win the inaugural MotoGP Thailand Grand Prix to extend his championship lead to 77 points.
Scorching temperatures led to a steady first half of the race, before Marquez and Dovizioso engaged in another battle in the latter stages, with the Honda man coming out on top by just 0.115 seconds.
Marquez took the lead on the run into the first corner after launching from pole, with Valentino Rossi heading Cal Crutchlow and Dovizioso.
Dovizioso used the grunt of his Ducati to pass Crutchlow for third into Turn 3, while Rossi took the lead from Marquez at the start of the fifth lap, with Dovizioso demoting the Honda rider further at the end of the tour.
For the next six laps, the leading group ran line astern behind Rossi and extended to eight riders at one stage, before a poor exit from the first corner on lap 11 allowed Dovizios and Marquez to breeze past.
With 10 laps remaining, the top three began to break from the group, while Dani Pedrosa and Maverick Vinales cut their way into the top five.
Pedrosa's charge for a first podium since Valencia last year came to a sudden end at Turn 5 with eight laps remaining when he crashed.
With four laps to go, Marquez made his first assault on Dovizioso's lead at Turn 3, but ran wide and let the Ducati rider back through.
This allowed Vinales, who passed teammate Rossi several laps prior to lead the Yamaha charge, to close in and shadow the duo through to the chequered flag.
Marquez made a second raid with a daring move at Turn 8 a lap later, but Dovizioso retaliated on the inside of Turn 9, with the pair swapping positions twice across the penultimate lap.
Dovizioso led across the line to start the final tour, with Marquez scything up the inside at Turn 5. Dovizioso launched a final attack at the final corner, but Marquez nailed his exit to claim his seventh win of the year.
Now 77 points clear of Dovizioso, Marquez heads to the next round in Japan with his first match point in the 2018 championship battle.
Vinales crossed the line 0.270s back from the win for his first podium since Germany, with Rossi and Johann Zarco completing the top five.
Suzuki's Alex Rins' early charge stalled at sixth, while Crutchlow rapidly dropped off the pace late on to end up seventh on his LCR Honda. Alvaro Bautista, Danilo Petrucci and Jack Miller completed the top 10.
Andrea Iannone got his Suzuki home in 11th ahead of top rookie Hafizh Syarhin on the sister Tech3 M1. Aprilia's Aleix Espargaro, the only rider to run the soft tyre, was 13th from Marc VDS' Franco Morbidelli and top KTM runner Bradley Smith.
