Giovanni Canaletto, a full-brother to Derby winner Ruler Of The World, has met with setback, but the Ballydoyle handler will still be well represented at Chester and Lingfield this week.
“Giovanni Canaletto has scoped badly and it’s a bad time to get a setback,” said O’Brien.
“Sir Isaac Newton (second to Zawraq on his only outing) will run in a maiden at Chester (Wednesday). He has a lot to learn in a short time.
“Smuggler’s Cove (third in Dewhurst) will go for the Dee Stakes (Friday) and we’ll run something in the Vase.
“Order Of St George will probably run in the Lingfield Derby Trial (Saturday).
“John F Kennedy will run at Leopardstown on Sunday (in the Derrinstown Derby Trial). He needs to go, and hopefully the ground won’t be too bad.”
O’Brien also had news of Ol’ Man River, who was last of 18 in the Qipco 2000 Guineas at Newmarket.
“Ol’ Man River is OK after the Guineas and he might go for the Dante.”
Meanwhile Zawraq could skip the Derrinstown Derby Trial this weekend if the ground is too soft.
Dermot Weld’s colt is prominent in the betting for the Investec Derby after a brilliant display on his seasonal reappearance.
Regular rider Pat Smullen is also suspended this weekend and Weld is giving serious consideration to running him in the Irish Guineas if he does not run on Sunday.
“We will make a decision during the week about Zawraq. We will see what the weather does and what the ground is like,” Weld said.
“He could run in the Irish Guineas (if he does not run this weekend). There’s been no decision yet.
“The fact Pat can’t ride him affects our thinking slightly but the main thing is the weather, we’ll see how soft the ground is and see how he works this week.
“He’s been satisfying me at home, but he’s very laid back.”
Fillies’ Mile winner Together Forever is one of 18 possibles for Saturday’s Betfred Mobile Oaks Trial Stakes at Lingfield.
Aidan O’Brien has entered two, with the other being Wedding Vow, last seen chasing home subsequent 1000 Guineas winner Legatissimo.
Supreme Occasion, a close fourth in the May Hill last year behind Agnes Stewart, may make the journey south for David O’Meara. Pandora, impressive on debut for Charlie Hills, has been given the option, as has Paul Cole’s Newbury winner Jasmine Blue. Affileo, who is declared for the Cheshire Oaks, Maybelater, Bellajeu and Nadder are all among the entries.