Trained by Joseph O’Brien and ridden by his brother Donnacha, Speak In Colours was a 4-1 shot for this six-furlong Group Three.
The three-year-old was being pushed along from an early stage, seemingly struggling to keep up with the strong early pace.
However, he stuck to his guns to stay in the hunt and finished well to get up and beat admirable veteran Gordon Lord Byron by a length and a quarter.
Spirit Of Valor, the 6-4 favourite, was third.
The winning handler said: “He had a couple of nice runs earlier in the year. He was a bit disappointing in Ascot (unplaced n the Commonwealth Cup), but that was a funny race and it’s nice to get him back on track today.
“He had good form on good ground as a two-year-old, so we weren’t worried about that and it was a pretty quick time.
“Donnacha said he was happy throughout. He said he put him in gear and he got to the front a bit sooner than he wanted, but he was comfortable the whole way.
“He has Haydock and all those options. We wanted to get today out of the way and now we’ll talk to the owners and see from there. He handles an ease in the ground too.”