As the lights went out it was Danilo Petrucci (Alma Pramac Racing) who got a lightning launch from P8 to head around the outside and lead into Turn 1, but the Italian then ran off at Turn 2 to end his charge.
However, fellow Alma Pramac Racing rider Jack Miller took advantage to take the lead of his home Grand Prix at Turn 4 - a rinse and repeat of 2017 for the Aussie.
Pole man Marc Marquez (Repsol Honda Team), who crashed later in the race, slotted in behind Miller with Iannone third, but heading into Turn 1 on Lap 2 it was all change:
Marquez took over the reins of the freight train, with Dovi slotting into second, Iannone third and Miller pushed back to fourth. as the riders were in close pursuit of each other.
Vinales was in the groove and looked like he was on rails around the Island. Rossi was leading the chase before Iannone then took the baton, but the Suzuki man ran wide at Turn 4 and dropped to the back of the quartet.
Alvaro Bautista (Ducati Team) was taking no prisoners on his one-off Ducati factory ride, with he and team-mate Dovi also taking it in turns to try and reel in Vinales.
But no matter who it was out of the four, no one could match the Spaniard's superior pace - the gap was 1.9 seconds on Lap 13, and grew to four seconds by Lap 21 as he held it along.
The number 25 finally ended Yamaha's 25-race losing sequence in style, withIannone taking second and Dovizioso finishing third for his first Phillip Island podium in red.