The shape and structure of two Stakes races will determine where a quartet of Ciaron Maher and David Eustace three-year-olds start the autumn campaigns.

King Colorado, Brave Mead, Southern Tycoon and Scentify are entered for the Group 3 Manfred Stakes (1200m) at Caulfield on Friday along with the Group 2 Australia Stakes (1200m) at Moonee Valley on Saturday.

Maher said the quartet could be among acceptors for both races before barrier draws are taken into consideration.

"If you've drawn 10 in one and two in another, then it might be an easy decision," Maher said.

"But it will all depend on the shape of the race and what accepts where."

The Maher and Eustace stable also has older horses Nugget and Recommendation entered in the Australia Stakes, with Maher saying the latter galloper was possibly the only certain starter in the Group 2 contest.

Maher said of the three-year-old brigade, King Colorado could take on the older horses, having experience against all-comers, while Scentify has performed well at The Valley.

King Colorado has not been seen since finishing last behind Romantic Warrior in the Cox Plate (2040m) at The Valley in October which followed a solid fourth behind stablemate Griff in the Caulfield Guineas (1600m).

Maher said the Group 1 Australian Guineas (1600m) at Flemington in March was King Colorado's main autumn goal.

"He was always a bit casual last time, but he seems a lot more professional this time around," Maher said.

"We rode him forward in the Cox Plate as you generally do when you get that sort of weight pull and it probably wasn't to his liking.

"He was a great run in the Caulfield Guineas and will only be better suited at Flemington.

"Eagle Farm suited him, a big wide-open track where he can open up and Mark (Zahra) is pretty keen to ride him.

"He's tackled the older horses once or twice while Scentify is probably a sharper horse than King, and has a good record, so he could be one that goes to The Valley."