Who Shot Thebarman will continue his remarkable record over the marathon flat trip when the New Zealand-bred and owned stayer fronts up in Saturday's $A2 million Gr.1 Sydney Cup.

It will be the durable gelding's fourth appearance in the Randwick event having finished unplaced in his first attempt in 2014, runner-up the following year and fourth 12 months ago.

Who Shot Thebarman has also run in three Gr.1 Melbourne Cups – third in 2014, unplaced in 2015 and fifth last year – and he won the Gr.1 Auckland Cup in 2014.

"To be having his eighth two mile run is really something," part-owner Dan O'Leary said. "Not many horses can compete like he can."

Trained by Mark Oulaghan for his first two 3200 metre appearances, Who Shot Thebarman has since been in the Sydney stable of Chris Waller.

"He's pretty happy with the horse and everything has gone to plan," O'Leary said. "I was there for the BMW and I thought it was a very good run."

After a first-up third in the Gr.1 Chipping Norton Stakes and sixth in the Gr.3 Sky High Stakes, Who Shot Thebarman then finished fourth in the GR.1 BMW.

"It would be good if the track dries a bit during the week, it would improve his chances," O'Leary said.

"With his topweight (57kg) on heavy going it would be tough work. The better the track, the better his chances."

Who Shot Thebarman is a rising nine-year-old and some thought has been given to life after Group One company for the son of Yamanin Vital.

"He jumped at home before he went over to Sydney – he's a very good jumper," O'Leary said.

"It remains to be seen what happens, that's in the background as there's still good money on the flat even if it's not at that top level."