Confirmation that the Guineas hero Dawn Approach will attempt a classic follow up in the Derby won't prevent Aidan O'Brien from trying to generate a powerful Epsom challenge of his own in the coming week.

Four successive days of Derby trials, beginning on Thursday with the Chester Vase, will see the champion trainer test the blue-riband credentials of his Ballydoyle blue-bloods.

O’Brien yesterday nominated Ruler Of The World as a likely starter in the Vase and confirmed Battle Of Marengo, a general 5/1 second-favourite for the Derby in ante-post betting, will take his place in Sunday’s Derrinstown Trial field at Leopardstown.

In between, Magician is being targeted at Friday's Dee Stakes in Chester while Nevis is a possible for Saturday's Derby Trial at Lingfield.

However, one Ballydoyle star that looks to be out of the Epsom equation is Kingsbarns, winter-favourite for the Derby but plagued with injury problems during the spring.

O’Brien isn’t definitively ruling him out of Epsom just yet but conceded: “We’ll see, but I wouldn’t say he’ll be ready in time. He is 20 kilos above his racing weight. He’s been doing so little for so long he looks like a sprinter.”

The task facing Dawn Approach's Derby opposition though was emphasised yesterday when the Turf Club's flat handicapper Garry O'Gorman said Jim Bolger's unbeaten superstar is now officially rated 125 after his brilliant Newmarket success.

Ratings
"That's second only to Frankel in terms of Guineas winners since 2000," O'Gorman said. "Both Kings Best and George Washington were rated 124. Camelot originally got a mark of 122 after the Guineas last year but that performance ended up being rated 119 which is at the lower end of the scale."

There could be classic clues too at Navan this evening where the Ballydoyle hope Magical Dream, who holds Oaks entries, carries a Group Three-winning penalty in the Listed Salsabil Stakes.

The form of Magical Dream's Park Stakes win has been boosted since, as has her Moyglare fourth to Sky Lantern. Even with a penalty, the balance of that form looks tough for the impressive Cork maiden winner Alive Alive Oh to cope with.

Canary Row could reverse form with Dibayani while Friday's Dundalk winner Above The Law could still be well ahead of the handicapper in the opening sprint.