Serpentine only won his Maiden seven days ago and was racing for just the third time on Saturday but produced an extraordinary performance to win The Derby (12f) at Epsom.
Allowed a comfortable lead at a steady speed, Emmet McNamara asked Serpentine to quicken beginning the descent to Tattenham corner and was at least 12 lengths clear and in full flight into the home straight.
Needing only the occasional reminder, Serpentine (25/1) galloped all the way to the line to defeat the 50/1 chance Khalifa Sat (Free Eagle) by 5-1/2 lengths with Amhan Na Bhfiann (Galileo) a half length further back in third, the 5/2 favourite Kameko a nose away in fourth.
McNamara told ITV he was surprised at the way he was allowed to lead so easily.
“I think I got a little bit of a freebie really,” McNamara said. “I had a huge amount of confidence in the horse having spoken to Aidan during the week, he said he thought the horse would stay a mile and six furlongs well.
“He told he to give him a breather around the six-furlong mark and then to keep building to that winning post because the horse would keep going, thank god he was right.
“I couldn’t hear a thing, I could just hear the horse breathing, he was in a good rhythm, he was relaxed. I couldn’t hear a thing around me, I didn’t want to be looking, I wasn’t aware of it, I knew I was a few clear alright – it’s surreal to have won this race, I can’t believe it.”
It is the eighth Derby win for O’Brien, who was celebrating a rapid Classic double following Love’s comfortable victory in the Oaks earlier in the day.
“It’s unbelievable really, we always thought he would stay very well,” he said speaking by phone from Ireland,
“He won at the Curragh last week over a mile and a quarter and Wayne (Lordan) said he galloped right through the line and he couldn’t pull him up. I am delighted for the owners as this is obviously another Classic-winning homebred by Galileo.”