“Don't change your tactics, drop her out the back and pray,” said the legendary jockey, 40 years after his third win in the race aboard the mighty Alleged.
But the prayers were not answered in Paris on Sunday. Instead, Haggas hearts were broken in a city renowned as the most romantic in the world.
While Enable was greeted by green traffic lights all the way, Sea Of Class was obliged to race wide and encountered stop signs and slow-moving traffic at every turn. Despite weaving through and finishing with a flourish, the finishing line came a stride or two too soon for her.
“In the last 50 yards we were on our hands and knees,” Frankie Dettori admitted but he and Enable clung on by a short neck.
So close, yet so far for the aptly named filly who almost wrecked her party.
Racing UK asked its Twitter followers to judge whether she was an unlucky loser. We got more than 1,300 responses in an hour and 62 per cent said she had been.
Perhaps Enable’s supporters were too busy celebrating to cast their votes, but it gives you an idea that the result of the 2018 Arc might well have been different had the runner-up enjoyed just a little more good fortune.
And maybe there would have been more acknowledgement of that had the winner been anything but Enable, a wonderful thoroughbred with a deservedly huge public following.
"She's got beaten by a champion, Enable is a great horse," William Haggas said. "Maybe people will look back and say the draw didn't help us. I don't want to be ungrateful or unsporting."
His emotional wife said: "She's run a brilliant race and we're absolutely thrilled to bits with her. I'm just sad for James, who made such an effort to get the weight off and had done it.
"From that draw she's run unbelievably well and just didn't quite get there. From where he was drawn he had little alternative really.”
She added: "You can't be disappointed in any way, but I'm sad, for everybody really, as she's pretty good and she's got beat. She's had a brilliant year and let's hope she can come back and do similar next year."
Doyle was also philosophical. "She did everything I asked and just cruised through and in another three strides we would have won.
"I thought she struggled slightly with the ground at the start, but it was always going to be hard from that draw. I hope she can come back next year."
Christopher Tsui, who owns Sea Of Class with his mother, Ling, said: "I am still shaking as the emotions are running high, the way she finished reminded me of Zenyatta.
"When you look at how much ground she made up, it's easy to say we were unlucky, but in racing these things can happen.
"It's too early to say about next year, but we shall certainly think about it."
Select any odd to add a bet