Only the barest of margins was the difference as John Size pulled off the best training performance to not win a Group One yesterday at Sha Tin and three world class jockeys got the Stewards’ Cup finish wrong.

Richard Gibson-trained Giant Treasure (Christophe Soumillon) had his grey head out at the right moment to outlast the John Size-trained pair of Luger (Zac Purton) and Contentment (Joao Moreira), but the winning rider would have saved cheaply.

“Christophe congratulated me, Joao congratulated me – I thought I had won by half a neck,” said Purton.

WATCH: The post-race interviews with Giant Treasure's jockey Christophe Soumillon and trainer Richard Gibson

“I was so surprised to come back in and find out he had been beaten, I couldn’t believe it. It was a great training effort again, first-up over a mile against top class horses that are already race fit. At the 200m he was starting to feel the pinch a little bit but his heart is so big that he gave everything he had.”

That big heart had been the problem – some opinions draw a correlation between that and atrial fibrilliation in racehorses – leading to Luger’s comeback after nine months away due to his second heart arrhythmia in May.

He failed by a short head to land the most unlikely of Group One doubles, an hour after Purton had won the Centenary Sprint Cup on Aerovelocity – also returning from a heart irregularity-enforced break.

“I thought both Luger and Contentment were perfectly ridden, had their chance – everything was right except the result,” said Size, who poured cold water on the notion Luger would improve greatly.

“He was fresh, as you’d expect, and looked a touch keen down the back, but I don’t know how much better he’ll be for it. The main thing is that he has put in after such a long break and that’s all you can ask.”

But the day belonged to Giant Treasure and Gibson, who has been racking up seconds this season, had finished runner-up on international day in two Group Ones and probably saw it happening again after Gold-Fun’s second earlier.

“He ran fantastic in the Hong Kong Mile and we knew if he repeated that he’d be tough to beat,” Gibson said.

“Last year, we always knew he had bags of talent and now he’s doing it at the top level. The blinkers have definitely helped, Christophe has improved the horse too, and he thinks he’ll run further.”

Soumillon said Giant Treasure was a difficult ride with mental quirks he is only now working out after three rides on him.

“When I rode him the first time in November, you can feel has lot of ability but is not trying that hard,” Soumillon said. “You need to bring him into the race at the right part, he loves to come through horses.

“In the Hong Kong Mile, I rode him for a place and he responded and I did the same today – if you ride him like a usual horse, come outside and try to win it ... well, you see today he hit the front, he looked around and I couldn’t make him concentrate.

“He was lucky to not get beaten, but I do think he’ll run further and the Dubai Turf could be a good race for him.”

Behind there were so many good runs from Beauty Only, Blazing Speed, Military Attack and Designs On Rome – setting up a deep clash in the Hong Kong Gold Cup later this month.