Form cross references are not infallible, but they work in more cases than not.
The clear one heading into tomorrow's A$6.2 million Emirates Melbourne Cup is Hartnell's thrashing of Jameka in the Turnbull Stakes a month back.
Jameka came out two weeks late and dealt similar destruction on the Caulfeld Cup opposition.
But, cross referencing the form of the 11 Northern Hemisphere Melbourne Cup horses has proved a dangerous exercise for more than a decade.
We have seen impressive form from stablemates Qewy and Oceanographer in winning runs since arriving in Australia and they are right in contention tomorrow.
Bondi Beach, Big Orange, Almadin, Heartbreak City, Curren Mirotic and Sir John Harwood have not been seen on this trip and only the first two raced in last year's Melbourne Cup before returning home.
So here is how we rate them in order of preference:
$6 Oceanographer: Has not raced beyond 2800m, but the way he finishes suggests the 3200m will be no problem. Could not have been more stylish in flashing home from near last to win Saturday's Lexus to force his way into the Cup. Has a light weight 52kg, the No 11 barrier, which happens to be the most successful of all barriers. Tough to beat.
$9 Bondi Beach: Owned by Lloyd Williams in Australia, but trained in Ireland by the master, Aidan O'Brien. Ran in last year's Melbourne Cup as an inexperienced horse. Has had a carefully planned attack for this race.
$16 Big Orange: Led them up in last year's Cup and finished a brave fifth. Lead-up European form this time looks superior to 12 months ago. The problem could be the 57kg topweight, which will make the job of leading this time fairly difficult.
$15 Heartbreak City: Came off two hurdle wins in Ireland to win the highly-regarded Ebor on the flat at York. Has a horror No 23 barrier draw, but has a genius in Joao Moreira on his back to overcome that.
$18 Wicklow Brave: Trained by the canny Willie Mullins in Ireland. Came off some mixed form to win one of the big ones, the Irish St Leger last start on September 11. Has the terrible outside draw and Frankie Dettori has a job on his hands. Like Moreira, on his day Dettori can weave magic.
$31 Curren Mirotic: The sole Japanese runner. Form has been hugely inconsistent and his last win was more than two years ago. Tommy Berry will go forward on him from his wide gate and that's the way Japanese stayers race best.
$21 Qewy: Stablemate of Oceanographic. Beat him in the Geelong Cup, but Oceanographer was flashing at him late suggesting over this distance those placings should be reversed.
$31 Grey Lion: Raced on the speed and fought well for second to Qewy in the Geelong Cup. Faces a tougher test this time, but has a light 52kg.
$35 Secret Number: On second Australian trip. Raced just once last year when favourite for the Queen Elizabeth with and finished a good second to Dandino. Has raced only once since for a win at Ayr. Would be a magnificent training effort if he won, but has ability.
$61 Beautiful Romance: Beaten in easier races in the UK before heading to Australia. The odds reflect his chance.
Who measures up?
Hartnell would appear to have the best credentials of the locals.
Bondi Beach is the highest rated by bookies of the northern contingent.
Ebor Hcp winner Heartbreak City could be the surprise factor.