There are 16 two-year-olds set to face the starter in Saturday’s Group 1 Blue Diamond but recent history suggests we can prune back the field to a handful of chances.

For starters, the lead-up form of Blue Diamond winners over the past decade or so has been remarkably consistent.

Of the past 13 Diamond winners, 10 have finished first or second in a Preview or Prelude at their final lead-up start.

The other three have won the open-sex black-type two-year-old race run in Melbourne three weeks before the Diamond. In the case of Sleek Chassis (2007) and Star Witness (2010) that was the Talindert Stakes, but after a calendar change it’s now the Chairman’s Stakes, won in 2016 by subsequent Diamond winner Extreme Choice.

This year’s MRC Chairman’s Stakes was won by Mildred, who raced last Saturday at Flemington and won’t be backing up in the Diamond.

More generally, all Diamond winners since 2004 have been having either their third or fourth race start.

The 2003 winner, Kusi, was having just his second start in a race, but you couldn’t have collected on him anyway. Roedean (having her third start) was first past the post but later disqualified on a positive swab.

Kusi was also the last gelding to win the Blue Diamond. The last gelding to be first past the post was Road to Success in 2000.

Sadly, that particular fun fact doesn’t help us because there are no geldings in Saturday’s field.

So where does that all leave us? With (drumroll) Hanseatic, Rulership, Letzbeglam and Muntaseera. If you extend the criteria to include the Chairman’s Stakes runner-up, you can throw in Aryaaf.

Narrowing the chances down to five is not much use if the $2.40 fave gets up, but the winner’s average price over those past 13 Diamonds has been $6.48.