Rea made the best getaway from the outside of the front row when the 21-lap race got underway on a wet track, dropping the BMWs of Tom Sykes and Eugene Laverty to second and third respectively.
GRT Yamaha rider Garrett Gerloff also tried to pass the BMW duo by making a lunge into Turn 1, but in doing so he hit Sykes’ bike and sent him straight into the path of Laverty.
Both BMWs were eliminated from the race in the incident, while Gerloff held control of his Yamaha to slot into third behind race leader Rea and Alex Lowes.
On lap 2, both Gerloff and Ten Kate Yamaha’s Loris Baz cleared the second Kawasaki of Lowes and joined Rea in a three-way battle for the lead.
Baz took advantage of a wide moment for Gerloff to move up to second and then started hunting down Rea, while Gerloff positioned himself behind the leading duo in third.
On lap 5, Baz dived down the inside of Rea at the Adelaide hairpin, but Rea got a better exit out of the corner to retain the lead.
Two laps later, Gerloff suffered a major highside coming out of the Turn 6 kink and crashed out of the race, leaving Rea and Baz to battle it out for victory.
Baz initially stayed close to the tail of Rea’s Kawasaki, but Rea put the hammer down on lap 14, pulling 1.8s clear of the Frenchman.
He eventually won the race by a comfortable margin of 3.3s, scoring his 98th career win and putting himself one step closer to clinching his sixth world title.
Lowes couldn’t match the pace of the leading duo, but third place marked his first podium finish since his victory in Phillip Island back in February.
Chaz Davies was the top Ducati runner in fourth, but ahead of the battling duo of Yamaha’s Toprak Razgatlioglu and factory teammate Scott Redding.
Razgatlioglu was fighting with the Honda of Leon Haslam in the final stages of the race, which also allowed Redding – who trailed in 10th place at one point – to join the battle.
Haslam was leading the trio on the final lap when he suffered a highside in the wet conditions at Turn 12, allowing Redding and Razgatlioglu up to to fifth and sixth respectively.
Michael Ruben Rinaldi was classified seventh on the Go Eleven Ducati, while the top 10 was completed by Xavi Fores on the Puccetti Kawasaki, Yamaha’s Michael van der Mark and Motocorsa Ducati’s Leandro Mercado.
With Haslam retiring from the race on the final lap, Alvaro Bautista finished as the top Honda rider in 12th, 46s down on race winner Rea.