The first nine days in September will be definitive in determining which European horses race during the 2021 Melbourne Spring Carnival.
The challenge for horses and staff to arrive from overseas has never been greater, complicated by new pre-travel veterinary protocols and further exacerbated by COVID-19.
Racing.com understands about 11 Northern Hemisphere horses remain in contention for a trip to Melbourne via Werribee's International Horse Centre this spring.
All horses seeking to travel on the first shipment have undergone the much-publicised full body scintigraphy and CT/MRI of distal limbs, in anticipation of travelling to Melbourne.
Thursday looms as D-Day for these first-shipment travelers, with connections of the respective horses due to be informed that day by Racing Victoria whether their horse has cleared the veterinary screening process.
Connections of the scanned horses don't expect to hear any bad news later this week from RV.
There is, understandably, some teeth chattering from connections given it's the first time the veterinary process has been performed to such an extent.
Should pre-travel veterinary clearance be granted, the next complication will be getting travelling staff from Europe to Melbourne on connecting flights in time.
Last year, travelling staff arrived in Sydney and completed two weeks' quarantine before driving across the Victorian border.
That is not possible this year as current COVID-19 regulations require individuals to be given special exemption to cross the Victorian and New South Wales border to complete an additional fortnight of quarantine.
Racing.com has been told by multiple sets of connections that more incoming overseas passenger flights are arriving in Sydney, albeit still on a limited basis, rather than Melbourne.
RV is working with stables to secure flights for travelling staff. Some stables are still looking for flights, which threatens to delay or jeopardise their horses arriving in Melbourne.
Travelling staff for horses on the first shipment must be in Melbourne and starting their hotel quarantine from September 9, the same day horses will start their fortnight quarantine in Newmarket, in order to be available to care for them upon arrival at Werribee on September 25.
Australian Bloodstock purchased a half-share of Rodrigo Diaz from Quantum Leap Racing ahead of his second to Hukum in the G3 Geoffrey Freer Stakes (2671m) at Newbury on August 14.
"The big issue is whether we can get staff out here," Australian Bloodstock co-director Jamie Lovett said. "David Simcock (trainer of Rodrigo Diaz) is struggling to get these guys on an aircraft, so it will depend a lot on that."
Connections are eager for Rodrigo Diaz to arrive on the first shipment and have a lead-up start ahead of the Melbourne Cup, which will help him secure a spot in the field.
However, should travel arrangements not be finalised in time for Simcock's staff, Rodrigo Diaz would contest the G2 Doncaster Cup (3600m) on September 10 and then attempt to travel on the second shipment for the Melbourne Cup.
Seven-time Melbourne Cup-winning owner Lloyd Williams is keen for Twilight Payment to contest the Caulfield Cup ahead of the Melbourne Cup but acknowledged the difficulty of getting foreign staff into Melbourne.
"As things are, it's a lot easier if I had a horse running in Sydney," Williams said.
That's the option taken by OTI Racing, who will have no horses coming through Werribee. OTI's Mirann and Win O'Clock will be trained by John O'Shea and prepared for the $500,000 Rosehill Gold Cup on October 30.
Mirann was once touted as a Melbourne Cup prospect before his stamina limitations were exposed in this month's Ebor Handicap (2787m) and he was redirected towards Sydney's Everest Carnival.
The second shipment arriving in Melbourne on October 12 will also contain foreign horses bound for Sydney and arriving on the same day.
O'Shea will also welcome Maximal into his care at the same time, with his Cox Plate nomination set to be forfeited in preference to the $7.5m Golden Eagle (1500m) at Rosehill on October 30.
Then there's the case of three-time Melbourne Cup placegetter Prince Of Arran, who will race for the first time since late April in Saturday's G3 September Stakes (2413m) at Kempton.
Trainer Charlie Fellowes submitted Prince Of Arran to undergo the full body scintigraphy to allow him the option of travelling on the first shipment and the possibility of a lead-up start in the Caulfield Cup ahead of the Melbourne Cup.
However, any trip to Australia will be dependent on how the Northern Hemisphere eight-year-old performs on Kempton's all-weather track.
Below is an update on each horse who remains in contention for a trip to Melbourne.
STATUS OF POSSIBLE FIRST SHIPMENT ARRIVALS
Gold Trip (Ciaron Maher and David Eustace)
Connections are committed to running Gold Trip in the Cox Plate.
Twilight Payment (Joseph O'Brien)
Connections are keen to see him race in the Caulfield Cup ahead of another Melbourne Cup appearance.
State Of Rest (Joseph O'Brien)
Connections are keen to see him run in the Cox Plate.
Spanish Mission (Andrew Balding)
Connections eager to run in the Caulfield and Melbourne Cups.
Rodrigo Diaz (David Simcock)
Preference of connections is the first shipment, but should that not prove possible, would run in the G2 Doncaster Cup (3600m) and hopefully arrive on the second shipment ahead of the Melbourne Cup.
Prince Of Arran (Charlie Fellowes)
His performance in Saturday's G3 September Stakes (2413m) at Kempton will go a long way to determining whether he returns to Melbourne. Should he run well, the Caulfield and Melbourne Cups await.
Master Of Reality (Joseph O'Brien)
Unclear whether he would join Twilight Payment on the first shipment to Melbourne for a start in both Cups or may be a potential travelling partner for Baron Samedi on the second shipment on a Melbourne Cup raid.
STATUS OF POSSIBLE SECOND SHIPMENT ARRIVALS
Sir Lucan (Gai Waterhouse and Adrian Bott)
Scheduled to have his final start for Aidan O'Brien in the G1 St Leger (2921m) at Doncaster on September 11 ahead of the Melbourne Cup.
Sonnyboyliston (Johnny Murtagh)
Connections have decided that Sonnyboyliston will have his next start in the G1 Irish St Leger (2816m) at the Curragh on September 12. Any decision on a trip to Melbourne will be made following that race, or a possible sale to Australian owners.
Away He Goes (Ismail Mohammed)
Remains under consideration for a trip to Melbourne, where the Melbourne Cup would be his lone assignment.
Baron Samedi (Joseph O'Brien)
Could be considered an outside chance of travelling, with the sole intention of running in the Melbourne Cup.