Ranking racehorses with accuracy is a lot harder than other sports, where outcomes tend to be more predictable over time. There is less fluctuation in the rankings of top football, rugby, cricket teams, for example, and even individual sports like athletics, golf and tennis have relatively stable hierarchies.

Racing “chaos” is part of the game and can have us scratching our heads – witness the seasons-ending Champions Day at Ascot which threw up a few jolts. Palace Pier who was supposedly the worlds’ top miler got beat by emerging star, Baaeed in the G1 QE11 Stakes at Ascot; obscurely bred French invader, Sealiway toppled the big guns in the Group 1 Champions Stakes as Adayaar and Mishriff failed to place; 20/1 long-shot Eshaada won the G1 Champions Fillies and Mares Stakes with hot favourite, Snowfall (seen as a world beater a few months ago) a distant third.

There are so many variables in horse racing – perhaps one of the hardest for punters to assess is the shifting physical condition of each runner. Horses are constantly changing – either getting better or worse, with only a few staying at the same level over extended periods.

Together with the circumstances of each race being either subtly or dramatically different, many so-called form reversals can be explained after-the-event due to how the pace unfolded, luck in running or changes in the state of the going. And the margins, especially in turf racing are so small, with a split second the difference between success and “failure.”

Take The Tab Everest, the richest turf race in the World, staged Saturday at Royal Randwick in Sydney, Australia for prizemoney of $15 million. High class seven-year-old speedball, Nature Strip received a perfect pace-pressing ride to only just sneak in from a low flying Masked Crusader, who had to weave through the field from last place after bombing the start. A couple of centimeters meant a difference of many millions of Ozzy dollars!

Another illustration of how horses can get sizzling hot seemingly from out of nowhere is Caulfield Cup hero, Incentivise. He was beaten 16 lengths in a humble Toowamba Maiden in March and is now the 2.5 Melbourne Cup favorite after Saturday’s eye-popping win where he raced extremely wide from draw 20 for practically the entire 2400m journey yet still destroyed quality G1 opposition!

What makes it all so challenging is that punters are effectively trying to hit a moving target. Horses form cycles wax and wane, circumstances change and the margins between winning and losing are tiny. All smart bettors are constantly looking for an edge. They realize that certainties don’t exist, but prefer weighing up the probabilities, trying to peek into the future and then bet more strongly when the odds are deemed favorable relative to the anticipated outcome.