Reigning MotoGP champion Marc Marquez snatched the lead from Jorge Lorenzo on the final lap to win a thrilling Australian Grand Prix.
Honda's 22-year-old Spaniard, who started on pole, overtook his compatriot on the last turn to win his fifth race of 2015 by 0.249 seconds.
Lorenzo is now 11 points behind Yamaha team-mate Valentino Rossi in the overall standings with two races to go.
Rossi was narrowly beaten to third by Ducati's fellow Italian Andrea Iannone.
Seven-time world champion Rossi, 36, was racing in a record-equalling 328th grand prix. He was aiming for his 16th podium on his 19th trip to Australia but was ultimately unable to match Iannone's greater speed.
Marquez's win - his 24th in 52 race starts - was his first in a premier-class race at Phillip Island after he crashed out while leading last year and was disqualified in 2013.
It came at the end of an exhilarating battle between the top four riders, who were separated by just 1.058 seconds.
"During the race I felt well but at the beginning there were many overtakes between me, Valentino, Andrea and Jorge who opened some gaps," said Marquez, who had been fastest in all four practice and qualifying sessions and produced a track record of one minute, 29.280 seconds on the final lap.
"I didn't expect to overtake Jorge but I'm really happy with this victory because we've pushed really hard."
Cal Crutchlow finished seventh on his Honda, with fellow Britons Bradley Smith and Scott Redding 10th and 11th respectively.
|MotoGP world standings|
|1. Valentino Rossi (Italy)||Yamaha||296|
|2. Jorge Lorenzo (Spain)||Yamaha||285|
|3. Marc Marquez (Spain)||Honda||222|
|4. Andrea Iannone (Italy)||Ducati||188|
|5. Dani Pedrosa (Spain)||Honda||165|
Kent crash keeps Moto3 title race alive
Danny Kent is aiming to become he first British rider to win a grand prix championship in any class since Barry Sheene in 1977.
The 21-year-old could have sealed this in Australia, but spectacularly crashed during Sunday's race, allowing Portugal's Miguel Oliveira to win and narrow the gap between himself and Kent in the overall standings to 40 points.
Kent, who needed to finish in the top two to claim the world championship at Phillip Island, had a heavy fall on a bend on the 14th lap of the 23-lap race.
"I'm a little bit disappointed about the outcome. I felt really strong on the bike during every session and also in the race," said Kent.
"I felt very confident we could have left the island as champions. We need to keep working hard in the last two races, starting fully focused next week in Malaysia."
Kent can win the title in Malaysia with a top-five finish. Oliviera must get at least a podium place to take the fight onto the final race in Spain.
|Moto3 world standings|
|1. Danny Kent (Britain)||Honda||244|
|2. Miguel Oliveira (Portugal)||KTM||204|
|3. Enea Bastianini (Italy)||Honda||288|
|4. Romano Fenati (Italy)||KTM||165|
|5. Niccolo Antonelli (Italy)||Honda||161|
Rookie Rins wins in Moto2
Spaniard Alex Rins won the second race of his debut Moto2 season for Paginas Amarillas HP40 ahead of Speed Up Racing's Sam Lowes and Forward Racing's Lorenzo Baldassarri.
Rins is second in the world standings behind France's Johann Zarco, who has already claimed this season's title.