Red Cadeaux's historic Melbourne Cup bid had a familiar ending as trainer Ed Dunlop waited in the runner's up stall.

In his fourth appearance in Australia's most famous race, a record for a horse trained in the northern hemisphere, Red Cadeaux finished second for the third time.

"What a horse, hey. We can't win it though," UK trainer Dunlop said as he encouraged the Flemington crowd to cheer the veteran as he returned to scale.

Dunlop hasn't ruled out bringing him back next year.

"The winner was very good on the day, but yet again we finished second. What a horse. He's nine," Dunlop said.

"He hasn't shown much (this year) but we never lost the faith.

"My team have done it all. I've just turned up.

"We have an amazing horse and we're probably going to make another record now as the greatest bridesmaid ever."

Dunlop expected Red Cadeaux to run a big race because the horse had blossomed in Melbourne.

After hitting the front in the straight he was run down by the German-trained Protectionist which surged clear.

"We're always susceptible to these younger, up-and-coming horses and all credit to the winner, a beautifully trained horse that looks magnificent," Dunlop said.

"But we're very proud. We'll have to come back again."

Dunlop is considering a Sydney autumn campaign for Red Cadeaux.

And next year's Cup isn't out of the question but it's all about the horse.

"If he's still up to it, I'd like to come again because it's the greatest race in the world," Dunlop said.

"If he's not OK after today we'll retire him. It's as simple as that. It's up to the horse. Nothing else matters."