Ciaron Maher and Chris Waller are preparing to gang tackle the Doncaster Mile with the leading trainers set to have up to a dozen runners between them.

Both Maher and Waller each have five runners safely in the 20-horse field, along with an emergency apiece.

Maher's contingent includes $3.80 favourite Another Wil, while Waller's squad is headed by multiple Group 1-winning three-year-old Militarize, who is on the third line of betting at $8.50.

While Maher has firmly established himself among the top echelon of Australian trainers, he clearly remembers a time when that was still a dream, and says Another Wil is a horse close to his heart for that reason.

"I bought his mother (Arohanui) for $20,000 at the Melbourne Premier Sale and to say I was nervous was an understatement," Maher recalled.

"It was (at) $17, 500 and I was talking to (trainer) Aaron Purcell, 'do I bid? do I not?'

"I ended up buying her for $20,000 and she ends up being the mother of (Jericho Cup winner) Wil John and now Another Wil."

Maher will also be represented by Detonator Jack, Berkshire Shadow, Semana and Australian Guineas winner Southport Tycoon, while Nugget is first emergency.

The bulk of his horses handle rain-affected ground and Maher is bullish he has a strong hand.

"(Southport Tycoon) is very good. Nugget placed in the race last year, Detonator Jack ran a peach last start," Maher said.

"It's going to rain, 'Wil' handles it, 'Jack' handles it. There is a lot to play out but it's a good spot to be in."

Waller has Militarize, Kovalica, Zougotcha, Democracy Manifest and Lindermann, along with second emergency Hinged.

He has won the feature Mile six times, a trio of them with three-year-olds, and Militarize will be his representative for that age group on Saturday.

The colt boasts stronger formlines than Waller's previous three-year-old winners, but also the weight to prove it - he has 54kg, five kilos more than his Randwick Guineas conqueror Celestial Legend.

"He's a very good horse," Waller said.

"The others were probably more genuine handicappers, he's done it at two, he's done it three. He's a proper horse."

Militarize hasn't missed a place this preparation, finishing runner-up in the Apollo Stakes (1400m) and Randwick Guineas (1600m) and third in the George Ryder Stakes (1500m).

It is no coincidence he won the ATC Sires' Produce Stakes fourth-up 12 months ago and arrives at Randwick at his fourth campaign run, with Waller saying the key to winning a Doncaster is not only the right horse, but the right timing.

"You don't want them to be over the top, they've still got to be sharp but they've got to be fit enough and they've got to be a decent horse," he said.

"You don't really fluke Doncasters."