Red Cadeaux ($61), beaten by the smallest margin in Cup history two years ago, overcame a wide run to surge to the front at the top of the Flemington straight and fought a tooth-and-nail battle with Fiorente before the favourite overpowered him late in the race.
Dunlop admitted that he was concerned the horse was set for the retirement paddock before he arrived in Australia but was beaming with pride after such a brave run in the Cup.
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"I didn't really give him much of a winning chance, especially after drawing barrier 23," Dunlop said.
"After his latest run in Ireland I was considering whether this was going to be it for him."
"But would you put him out in a paddock after that run? He loves it here, dare I say we might come again."
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Red Cadeaux would be a nine-year-old should he return in 12 months' time but that doesn't concern Dunlop.
"I think it was an amazing ride with an amazing horse, at his age (eight) to nearly win another Cup," he said. "We bought the same horse here three times and we have been close twice.
"We won't be scared to come again."
Also contemplating another shot at a Melbourne Cup will be Luca Cumani, who watched Mount Athos improve on last year's fifth to finish third, yet another placing for the Italian trainer.
Jockey Craig Williams was apologetic to Cumani after the ride, where he got caught deep until the 1600m mark, and the hoop felt the barrier had made a major difference.
“His run was excellent. I drew 22 and the winner drew five, it’s a big difference. I had to do a little bit of work to get into a position and he ran great," he said.
"We made our run with Red Cadeaux and I didn’t think I had much left at the 200 metres and he was empty at the 100 metres and still ran on for third. Just heart and guts."
Trainer Willie Mullins said he was delighted with the performance of fourth-placed Simenon and he just didn't have the class to go with the first three horses.
At the other end of the field, Green Moon will be examined by vets after pulling up lame in what was the worst performance of his career. There is a strong chance the 2012 Cup champ will be retired.
Brown Panther, eighth, will also need treatment after he received cuts on his legs during the run.
In an eventful Melbourne Cup, which also saw European stayer Varema euthanized after she fractured a leg, jockey Rhys McLeod received a 10-meeting suspension for causing interference on Ethiopia.