Pint-sized Tasmanian three-year-old The Inevitable has upstaged a host of quality colts and geldings in his first Melbourne test at Flemington to deliver a thrilling win for his connections in the C S Hayes Stakes.

Ridden by Siggy Carr, who was competing at Flemington for just the second time, the Scott Brunton-trained gelding made it five-straight wins in Saturday's 1400m Group Three race on the undercard to the Group One Lightning Stakes.

"We're here at headquarters and we got the job done in a Group Three. It's my Lightning Stakes," Brunton said.

"He's a ripper."

The Group One Australian Guineas (1600m) at Flemington in two weeks now looms as the likely next target for The Inevitable whose four wins from his first five starts in Tasmania included the Listed Tasmanian Guineas.

The Inevitable has moved to $13 for the Australian Guineas with star Tasmanian filly Mystic Journey the $4.60 favourite.

In a tight finish, The Inevitable ($11) defeated leader Age Of Chivalry ($8) by a nose with third-placed O'Tauto ($10) another two lengths away.

Carr is unbeaten on The Inevitable from five rides and declared it her biggest win, having also won at Group Three level in a Hobart Cup and twice in South Australia.

"It's just a massive thrill," Carr said.

"Just to have the ride on him in this race today was big enough for me.

"He just felt the winner from the 600-metre mark and to have that feeling and be able to soak it up on the big stage like this, it's unbelievable.

"He's only a tiny horse and Scott has done a wonderful job with him.

"He's got talent there as he's shown today and it's a big buzz to be a part of it."

The Inevitable, by Dundeel out of Gift Bouquet, was a $90,000 yearling purchase in Adelaide in 2017 and has now earned $217,025 prize money from six starts.

Brunton said what also added to the victory was that he and Carr had grown up as childhood friends.

"It's a winning combination so why change it? And it puts a bit more meaning to it," he said.