The 23-year-old KTM rider, runner-up in the championship last year, grabbed the lead back on the final corner of the race for his fifth career victory and second place in the championship 28 points behind Spain's Bautista.

Aprilia rider Bautista, who won the first two races of the season and finished second in the third, was third behind his Italian team mate Pasini, who led for much of the latter stages of the race.

Swiss Thomas Luthi's miserable start to the defence of his world title continued when he retired after four laps, while the only Chinese in the race, Chow Ho Wan, crashed on lap seven and was disqualified six laps later.