Brisbane colt Ours To Keep has been heavily backed Australia-wide to win the Magic Millions Two-Year-Old Classic and could challenge for favouritism by race day.

As much as $10 was being bet by bookmakers about the Chris Munce-trained colt before Tuesday's barrier draw when he drew four.

However, the best price now available about Ours To Keep is $6 with most bookmakers having him at $5.50.

From Within, who will have to become the first horse to win the Classic at just her second start on Saturday, is a drifting favourite at $4.

Houtzen, who drew the outside barrier, is also drifting at a general quote of $4.40.

UBET's Nick Curry said the betting operator was offering $9 on Tuesday morning but Ours To Keep was quickly backed in to $6 and would continue to shorten.

"I wouldn't swap Ours to Keep for any other runner and don't write off my other horse Champ Elect either," Munce said.