Racing Victoria says it will be several weeks before it can release the findings of a report into the Melbourne Cup death of Irish stayer Anthony Van Dyck.

The cause of Anthony Van Dyck's fatal Melbourne Cup injury isn't expected to be known for weeks, the sport's governing body Racing Victoria says.

Anthony Van Dyck became the latest international star to go amiss in the Melbourne Cup when the Aidan O'Brien-trained stayer faltered late in the race.

As Twilight Payment swept to an all-the-way victory for O'Brien's son Joseph, Anthony Van Dyck was retired from the race with a fractured fetlock.

Anthony Van Dyck's injury was so severe that veterinarians were unable to save last year's English Derby winner.

Racing Victoria's Jamie Steir said a fatality report that included the results of an autopsy would be prepared as per the regulatory body's welfare protocols.

"The report will include the findings of a post-mortem which will now be conducted by the University of Melbourne Veterinary Clinic and we expect it will be several weeks before we have a completed report for consideration," Steir said.

On the strength of his placing in last month's Caulfield Cup, Anthony Van Dyck was one of the favourites at Flemington.

The Cup was a triumph for Ireland despite the shadow of Anthony Van Dyck's death.

In beating Anthony Van Dyck's stablemate Tiger Moth, Twilight Payment became the fourth Irish-trained horse to win Australia's greatest race - joining Vintage Crop (1993), Media Puzzle (2002) and Rekindling (2017).

It was a first Melbourne Cup win for 25-year-old jockey Jye McNeil.

But it was a seventh for leviathan owner Lloyd Williams, 40 years after winning his first.

Overseas horses dominated the finish with Prince Of Arran notching his third placing from as many attempts.

Jockey Jamie Kah insisted the English-trained warrior should have gone close to winning.

"He was super unlucky. He really deserves it. He just had no luck on the turn," Kah said.

As the heavily supported favourite Surprise Baby finished 13th, it was left to Persan from the Ciaron Maher and David Eustace stable to be the first Australian horse across the line in fifth.