Brazen Beau's connections remain confident the Australian sprinter can win the Diamond Jubilee Stakes at Royal Ascot after the race favourite drew barrier 15.

Trainer Chris Waller put the three-year-old through a quiet session on Thursday with the colt working at three-quarter pace over 800 metres.

"He looks great," Waller told AAP.

"I couldn't be happier with the way he looks and the way he's settled in."

Australia's leading Group One trainer insisted Brazen Beau was "ready to run a really strong 1200 metres" on Saturday.

"It's just the last 100 metres that's a query but we've done everything we possibly can to get him as fit as we can without actually racing," he said.

The colt will jump from barrier 15 of 15, but managing director of Ontrack Thoroughbreds which syndicated the colt, Grant Morgan, isn't too fussed.

"Brazen Beau down the straight at Flemington has won from an outside draw coming down the grandstand and he's also won from the inside," Morgan said.

"So he's got a lot of versatility, he's got a lot of tactical speed.

"Craig Williams has got the advantage of having a pretty clever horse underneath him so I think he can put him where he needs to."

Morgan said the horse was in "fantastic order".

"To my eye we couldn't think that the horse could be any better physically or mentally at this point," he said.

"Things have gone perfectly according to plan up until this point."

Brazen Beau will be up against the Gai Waterhouse-trained Wandjina in the Diamond Jubilee with some predicting an Australian one-two.

Aussie horses have performed well in the race previously with Black Caviar winning in 2012 and Choisir triumphing in 2003. Starspangledbanner, a dual Australian Group One winner for trainer Leon Corstens, won in 2010 for Aidan O'Brien after he was bought by Coolmore.

Morgan thinks Wandjina is better suited to the mile (1600m) but isn't taking him lightly.

"I think our horse is quite a bit sharper than him over 1200 metres but you can't underestimate the 1200 at Royal Ascot - it's more like 1400 in a lot of respects (due to the rise to the finish)," he said.

"So I've got no doubt if Wandjina can bring his top form he's going to be right there and one of the ones to beat."

Brazen Beau is set to stand at Darley's Northwood Park in Victoria in 2015 after a stud deal was finalised following his Group One Coolmore Stud Stakes win last spring.

But he could have one more race after Saturday.

"We're hoping we can get one more run out of him which would be the July Cup (at Newmarket)," Waller revealed on Thursday.

Morgan said any decision would be taken after Royal Ascot.

"(And) that will be more so an issue for Sheikh Mohammed and Godolphin other than us because our lease in the horse is up at the end of June," Morgan said.