The two Garry Rogers Motorsport teammates shared the front row for the start of the race, Cameron on pole and Herne alongside.
However it was Herne that got the swifter getaway, comfortably sweeping ahead of Herne as they went into the Senna chicane.
The lead GRM entries then looked to be the class of the field, Herne and Cameron running nose-to-tail as they easily gapped Joey Mawson in third.
Herne and Cameron's tense battle at the front last until Lap 7 when Cameron ran wide on the way into Turn 11.
As his car cranked sideways on the kerb it made contact with the wall and plucked the right-rear wheel off.
Cameron was able to immediately pull off to safety, preventing a safety car that would have erased Herne's significant lead.
With Cameron out of the picture, and Mawson still well over two seconds back, Herne was then able to cruise to a fourth Tasman Series race win from the four races so far.
Mawson kept his title hopes alive with a fourth second place of the campaign, while also setting a new outright lap record on the Adelaide Parklands circuit.
The previous record was a 1m17.972s set by Simon Hodge in a Formula 3 car in 2014, Mawson lowering the benchmark to a 1m16.815s.
S5000 cars now hold the lap record at Symmons Plains, Hidden Valley and Surfers Paradise, while also the unofficial record at Mount Panorama.
Cooper Webster was another 2.5s further back in third in Adelaide, while ex-Formula 1 star Giancarlo Fisichella took fourth place in what was his long-awaited S5000 debut.
The Italian did make a guest appearance in the series at Albert Park in 2020, only for the event to be infamously cancelled after qualifying on Thursday.
Jordan Boys came home fifth in the Adelaide opener ahead of Ben Bargwanna, Blake Purdie, Tim Macrow, Noah Sands and Jude Bargwanna.
Race 2 kicks off at 1:20pm local time tomorrow.
