Odds-on, look on. It's a phrase that was probably coined by some mug punter who'd done his last on the first odds-on favourite to ever go under a couple of hundred years ago.

But even its most faithful subscribers might be tempted to break ranks in Saturday's Tatts Cox Plate with the $3 million weight-for-age championship of Australasian racing appearing a put-in, take-out job with the Bart Cummings-trained So You Think seemingly over the line.

The defending Cox Plate champion hasn't been beaten in three starts this preparation, the most recent a three-and-a-quarter-length stroll in the park in the Group 1 Yalumba Stakes on October 9.

As a result, the $1.50 pop will go around the shortest-priced favourite in a Cox Plate since Tobin Bronze won at 1-6 - or $1.16 in current speak - in 1967.

But those who can't bring themselves to back something "in the red", there is telling statistic to at least give them hope that a few of So You Think's rivals are a chance of pulling off an upset.

Four-year-olds, who make up half of this year's field of 10, have a deplorable recent record in the Cox Plate. Four-year-old males have an even more lamentable record, stallions - of which So You Think is one - in particular.

Saintly (1996) was the last four-year-old male to win the Cox Plate, but the last four-year-old entire to win was Surfers Paradise in 1991. Two four-year-old mares have since won the Cox Plate, but none since Sunline in 1999.

They're worrying statistics, particularly when you consider that some pretty handy four-year-olds have been victims of the hoodoo.

Whobegotyou is the most recent, finishing midfield as the $2.80 favourite last year, a start after - like So You Think - winning the Yalumba Stakes.

He is one of many boom four-year-olds to go under as favourite, or near enough to, in the past 10 editions.

Miss Finland was fourth behind El Segundo in 2007, Racing To Win ran second-last at $3.80 the year before, Elvstroem and Starcraft fought out favouritism in 2004 but ran only eighth and third respectively behind Savabeel, while Lonhro beat just three home as $4 equal favourite in 2002.

The recent stats are remarkable given four-year-old horses have won more of the 89 Cox Plates than any other age group. They've won 25 with five-year-olds the next most successful at 22, while So You Think was the 19th three-year-old to win the race.

But none of the other 18 three-year-old winners are among the 11 horses to have won the Cox Plate more than once.

The trick is finding a horse to beat So You Think with his two main dangers - Sydney wonder mare More Joyous and AJC Derby winner Shoot Out - both also four-year-olds.

Captain Sonador and Trusting, the first two home in the Epsom Handicap, are the other four-year-olds in this year's Cox Plate.

That leaves Zipping, Whobegotyou, Luen Yat Forever, Wall Street and Avienus as the older horses in this year's 2040m race.

Only once has a nine-year-old won the Cox Plate, something Zipping needs to emulate, while Whobegotyou needs to pull off the seldom-achieved feat of winning the race the year after being beaten as favourite.

Wall Street is a classy six-year-old Kiwi with 10 wins from 17 starts, but failed at his only Australian run in this year's Doncaster Mile, while Macau raider Luen Yat Forever and Avienus were unplaced behind More Joyous in the Toorak Handicap and meet her significantly worse at the weights.

The more you look at it, the more it looks like the hoodoo will be broken this year. Perhaps, on reflection, the $1.50 about So You Think doesn't look such bad value after all.