Trainer Danny O’Brien has vowed that Vow And Declare will be an even better racehorse next year when he defends his Melbourne Cup title.

The Australian-bred, owned, trained and ridden Vow And Declare repelled the international invasion to deliver an all-Australian Melbourne Cup victory and a slice of history for jockey Craig Williams.

After a night celebrating with the horse’s Australian owners and family and friends, O’Brien is still waiting for the enormity of his first Melbourne Cup to sink in.

The Melbourne trainer is already targeting the 2020 Melbourne Cup for Vow And Declare.

“Next year I would say the most likely thing for him is that he comes back and has another go at it,” O’Brien told reporters at his Flemington stables on Wednesday..

“He’s only just turned four. He’ll be a better horse next year and he’ll need to be because he’ll have to carry more weight.

“Ultimately it’s a 3200-metre race that’s on just across the road from where he lives and it’s an $8 million race, so the most likely thing for us is that we’d try and see if he can win again.”

It was a first Melbourne Cup for both O’Brien and Williams, who joined an elite group of jockeys to win Australian racing’s “grand slam”.

O’Brien said the international raiders vying for the Cup had changed the race.

“It’s certainly a much more difficult race to win as an Australian than it was 10 years ago, let alone 20 or 25 years ago.

“It’s a very difficult thing to do, but it makes it incredibly satisfying when it happens.”

Vow And Declare pulled up well after the race, O’Brien said.

“We’ve both pulled up very well.

“He’s super.”

Only five horses in the Cup’s 159-year history have won the race twice – four of them winning back-to-back – including three-time winner Makybe Diva.

Williams became just the eighth jockey to claim Australian racing’s “big four” of the Melbourne and Caulfield Cups, Cox Plate and Golden Slipper.