Aidan O’Brien was left disappointed after star juvenile City of Troy failed to fire in the 2000 Guineas on Saturday, finishing ninth of the eleven runners.

Whilst the immediate reaction from connections suggested City Of Troy had become upset in the stalls, despite going in last, questions remain over the Justify colt's performance.

O'Brien said: "Maybe I left him too fresh, because he went into the stalls and reared up and when he hit the ground they let him go straight away.

"Usually what would happen when they'd rear up like that their heart rate would rise, but they'd usually get a second when they let them go back before they set off. But he went in, got upset and then 'bang', out straight away.

"His heart was probably very high, what happens usually those horses usually get into the red zone a lot quicker than they should. So probably he was in the red zone before halfway, so I'd say that's what happened. But because I'd left him too fresh, I was probably too easy on him and left him too fresh."

It was always the plan for City Of Troy to head to the Epsom Derby next, and O'Brien confirmed it remains the objective.

"He'll stay on the same path, you often miss the first one but we'll just put a line through it," he added.

"He'll go for the Derby, that's the pattern he was going and that's the way he'll go."

O'Brien is no stranger to working wonders from the Guineas to the Derby, having suffered the same crushing defeat in last year's 2000 Guineas before landing the Epsom Classic with Auguste Rodin.

City Of Troy is a general 6/1 shot for this year's Epsom Derby.