Champion jockey James McDonald has been left without a Melbourne Cup ride after dominant Cox Plate winner Via Sistina was ruled out of the race that stops the nation.

The Chris Waller-trained mare set a track record to win at Moonee Valley last Saturday in a performance that led to her being ranked the No.1 horse in the world.

Via Sistina immediately rocketed into Melbourne Cup favouritism, with her odds slashed to $5 despite not being a confirmed starter at Flemington on the first Tuesday in November.

Connections took their time to assess their options and on Wednesday ruled the seven-year-old out of Cup contention.

The news was announced by owner Yulong Investments via social media on Wednesday morning.

“Via Sistina officially ranked the world’s number 1 racehorse! The Cox Plate has always been her main target, to win it is nothing short of a dream,” Yulong said in a statement on X.

“Following this peak performance and after much consideration, it has been decided she will not contest the 2024 Melbourne Cup.”

Via Sistina will now target the Group 1 Champions Stakes (2000m) at Flemington on November 9.

The daughter of Fastnet Rock is an odds-on favourite for that race, with McDonald expected to be handed the ride.

A potential clash with last year’s Cox Plate winner Romantic Warrior in the Group 1 Hong Kong Cup (2000m) in December has been ruled out.

Earlier this week, Waller said he and connections would consider long-term prospects for Via Sistina when making a call on the Melbourne Cup.

“She seems fine, but you never really know until a few more days or even in fact until they run, so we’re just trying to preserve her to ensure that (Cox Plate performance) wasn’t just a one-off,” Waller said on Tuesday.

“My job, as the coach, is to get her to win not just one race but many races and to advise the people that own the horse what’s in her best interest.”

Via Sistina was bought by Yulong for $5.5 million in December last year and has now amassed more than $6.7 million in career prize money.

McDonald claimed his 100th Group 1 triumph in the Cox Plate with Via Sistina, winning Australasia’s weight-for-age championship for the third consecutive year after success aboard Romantic Warrior and Anamoe.

It remains to be seen if the 32-year-old New Zealand star will pick up a different Melbourne Cup ride.

Meanwhile, trainer Aidan O’Brien has conceded “rules are rules” after his three-year-old contender Jan Brueghel was withdrawn from the race on vets advice.

“He was a Group 1 horse in a handicap with 8st 7lb and Ryan Moore riding him. And he was getting better every week and he only ever won by very little. So that’s the way it is,” O’Brien told Racing Post.

“They made the decision and our vets didn’t agree with that.

“They said there was a shadow in front and a shadow behind, but every three-year-old at this time will have shadows and fissures and have this and have that.”