Champion trainer Chris Waller has declared Via Sistina primed for a crack at the Cox Plate, eager to turn a dramatic build-up into more success in Australia's weight-for-age championship.

Via Sistina sent a huge scare through the Waller camp four days out from Saturday's 2040m Group 1 feature at Moonee Valley, throwing jockey James McDonald during track work.

The pre-race fancy then galloped two riderless circuits of the track in an incident that initially prompted Yulong racing manager Troy Stephens to state it was "very unlikely" Via Sistina would start.

But Waller, who famously led super mare Winx to four consecutive Cox Plate wins (2015-2018), altered Via Sistina's preparation and has been thrilled with the response.

"She's bouncing, she really is," Waller said on Friday morning.

"She had very thorough trot-ups yesterday with Racing Victoria and she passed them with flying colours.

"She looks great, she's ready to go."

Waller sent Via Sistina for a quiet stint at the beach on Wednesday before a return to the Valley on Thursday.

"[That was] just to give her a good experience," he said.

"I didn't want her to be traumatised by it or have any negative effects to find out on Saturday when she went there that she would sweat up or be nervous in any way.

"That was fantastic. She just had a very quiet canter, one lap, and she was great. The recovery was good."

Via Sistina will jump from barrier four and Waller will also saddle up Kovalica (barrier nine), rating the latter only an outside chance.

"The draw makes it a little bit tricky and it's hard to say that he can beat those horses," Waller said, adding he has an eye on sending Kovalica to the Melbourne Cup.

"So we want to turn the race into a bit of a positive plus give him every possible chance to run as good as he can.

"We'll be aiming for a top-five finish, but most importantly finishing off strong.

"From barrier nine he'll probably go back and just need that little bit of luck, but if he gets that luck he's certainly a talented horse."

Waller's pair will line up in a small, yet highly competitive nine-horse Cox Plate field.

Japanese favourite Prognosis brings impressive form to Melbourne, while Ciaron Maher-trained Pride Of Jenni and the Hayes brothers' Mr Brightside will attract plenty of support.

Star three-year-old colt Broadsiding has won five of his last six starts, including three Group 1s, and is seeking redemption after falling short in the Caulfield Guineas.

Champion jockey McDonald will chase his third successive Cox Plate win aboard Via Sistina, having piloted Romantic Warrior and Anamoe in the past two editions.

AAP