One of the favourites for the Inter Dominions is set for a dramatic late stable change before the series which starts in Auckland next week.
But Marcoola will have to pass a veterinary examination today before his move to Hall of Fame trainer Barry Purdon is confirmed.
The national trot mile record holder will join Purdon for the series and possibly the entire summer if a endoscopic examination shows him to be clear of any issues after a disappointing performance in the $300,000 Dominion at Addington last Friday.
Marcoola lead and faded from the 400m in the Group 1 feature and even allowing for the solid tempo, he still performed well below his best.
That has led to today's examination, or scope as it is commonly referred to, in which Marcoola will be fast worked and have his airways checked immediately after.
"There have been a few horses down here struggling with a virus which is hard to detect," says unofficial co-trainer Clint Ford.
"We are not saying that was the problem last Friday but we want to check it out before we head north to make sure."
If he does come north Marcoola will join Barry Purdon and be trained wholly by him for the series which begins at Alexandra Park on Friday week.
"We are too busy down here with my work and other things to be away for five or six weeks, which is what it would be until the National Trot [December 31]." Ford said.
"So we have asked Barry to take him over so he has horses to work with, because when you work him by himself he can go a bit crazy.
"I will pop up and see him but if he goes to the series, which he will if be is virus-free, then Barry will be in charge."
Sheree Tomlinson, the grand daughter of Marcoola's trainer Ken Ford, will retain the drive in the series.
With exceptional trotter Oscar Bonavena to miss the Inter Dominion, the best version of Marcoola could return to favouritism for the final to be held on December 14, a rare Group 1 Saturday night meeting at Alexandra Park.
In a touch of irony, the horse who thrashed Marcoola and the rest of his Dominion rivals, Habibi Inta, will also be staying at Purdon's Clevedon property but in the care of his trainer Paul Nairn. Australian pacers San Carlo and My Kiwi Mate will also be based there.
The latter pair will be part of a seven-strong team of Australian pacers to tackle the Inters, joined by Colt Thirty One (Grant Dixon), Bling It On (Craig Cross), Our Uncle Sam (Chris Frisby), Atomic Red and Conviction (both Steve Turnbull).
The Australians will add a crucial new dynamic to the series, with their often aggressive racing style and are the silver lining of the series lacking a champion like Lazarus to scare them away.
The trotting series is likely to have three Australians in Tough Monarch, Big Jack Hammer and McLovin but the latter, who flew to Auckland last night, will need to please trainer Andy Gath in a workout tomorrow to prove he is over the thumps he suffered in the Dominion on Friday.
Stronger than expected local numbers from trainers like Purdon (three) and Steve Telfer (three) in the pacing series mean there is still a chance of three pacing heats on the three nights of the series but that would depend on how many remain in the series after the final payments this Friday.
Robert Dunn will have two in the pacing series and four in the trotters but one of the star locals in doubt is Star Galleria (Steven Reid) who underwent a veterinary examination yesterday.
The Auckland Trotting Club would ideally like to run three pacing heats per night but the cut-off for that would seem to be 27 horses so they could card nine-horse heats.
If the pacing series reduces to two heats per night they should at least have genuine depth and would raise the possibility of three trotting heats being held per night.
That series had 32 horses still entered yesterday but with a few lower-grade horses at the bottom. Again 27 acceptors would seem the cut-off for three heats per night or maybe even 30 for the trotters.
"We won't make any decision around that until we know final numbers and have spoken to the Inter Dominion council," says ATC president Rod Croon. "But we are thrilled to have the 10 Australians coming to really boost the series."
Inter Dominions return to Auckland
• The annual trans-Tasman harness racing series returns to Auckland next week for the first time since 2011.
• There will be three nights of pacing and trotting heats on November 29, December 3 and December 6.
• The $500,000 pacing final and $150,000 trotting final will both be on December 14.
• Seven Australian pacers and three trotters will contest the series.