Dunaden and fellow French stayer Americain went into the Melbourne Cup as the first two favourites and should have produced a quinella result.
Americain looked desperately unlucky to finish fourth after a less-than-inspiring ride by Gerald Mosse.
This was a magnificent combination of several participants all doing their job well and combining to lift one of the world's great racing prizes.
Delzangles held his nerve when his Geelong Cup-winning rider Craig Williams was suspended. The Frenchman had to sit on his hands until late on Monday to know whether Williams, or French jockey Christophe Lemaire, brought in from Japan in case, would ride his horse. For A$6.2 million ($8 million) that would unnerve most.
"It is all part of racing, you just have to deal with it," said Delzangles.
Lemaire, who had not been to Australia previously, did a magnificent job. "I was aware of not wanting to hit the front too soon, I was told that was suicide in this race.
"The horse in front of me, Corey Brown I think [Lucas Cranach], brought me into the top line at the top of the home straight but I held my horse back.
"Red Cadeaux got a neck on me, but I was always confident I could beat him." When you view the digital image of the finish - which held the racing world to ransom for so long - that seems an incredible statement.
And Lemaire might have been confident 200m out, but not so on pulling up.
"The person on the pony [clerk of the course] said he thought I'd won, but I like a lot of people to say so.
"When I brought my horse around the bend on trotting back the crown all said I'd won, so that felt a little better."
Lemaire said he and Red Cadeaux's rider, Australian Michael Rodd, wished each other well before they knew the official result.
The Frenchman said it was his second-biggest thrill in the saddle.
"Probably the only other occasion that matches this is when I won the French Oaks when all my family was there to see it."
Englishman Ed Dunlop, trainer of Red Cadeaux, was more relaxed than anyone who has previously finished a close second in a Melbourne Cup, but Michael Rodd was distraught.
PAY DAY
Emirates Melbourne Cup, $6,200,000, 3200M
2-2 Dunaden (3)... C Lemaire 1
18-18 Red Cadeaux (12)M Rodd 2
6-7 Lucas Cranach (9)C Brown 3
Scratched: Mourayan.
Also (in finishing order): 1-1 Americain, 8-9 Manighar, 15-15 Lost In The Moment, 13-14 Fox Hunt, 3-3 Niwot, 12-12 Unusual Suspect, 5-6 At First Sight, 11-11 Precedence, 10-10 Drunken Sailor, 20-20 The Verminator, 9-8 Tullamore, 17-17 Moyenne Corniche, 23-23 Saptapadi, 21-21 Older Than Time, 22-22 Hawk Island, 7-5 Illo, 4-4 Jukebox Jury, 19-19 Shamrocker, 14-13 Glass Harmonium, 16-16 Modun.
Nse, 1-1/4L, Nse. Time: 3:20.84.
Win: $8.20. Places: $3.10, $14.00, $4.50.
Quinella: $222.80.
Trifecta: $3643.60 (3,12,9).
First4: $21593.20 (3,12,9,1).
Treble: $177.00 (5/2/3).
Sub: Americain (1).
Trainer: Mikel Delzangles, France. Breeding: 6 h Nicobar (GB)-La Marlia (FR).
