Who will end up as O'Brien's highest-rated middle-distance three-year-old colt?
Anthony Van Dyck came out top in the Derby but will he prove the Ballydoyle best
Broome's Derby display was seriously impressive when you consider he was trapped wide throughout in the early stages and had to swing wide around Tattenham Corner to mount his challenge.
He stayed on powerfully up Epsom's long run-in and was showing no signs of stopping in the closing stages; had the race been another two furlongs the son of Australia would at worst have been in the first two.
It was a performance of a true St Leger horse, and with several of his stablemates likely to stay at a mile and a half or even drop in trip, Broome looks the horse to collect a fourth British Classic of the season for O'Brien.
The 1,300,000gns purchase looked outstanding in the paddock before the race and put in an excellent performance to finish third. He had just two behind him turning into the straight but picked up really strongly in the final stages despite Wayne Lordan dropping his stick.
The performance was a big step up on his Dante fourth and the highly regarded son of Galileo looks certain to make an impact at the top level. He is now a general 5-1 favourite for the St Leger.
Derby favourite Sir Dragonet may have suffered his first defeat on Saturday but there was plenty to like about his close fifth.
The impressive Chester Vase winner hit the front two furlongs out and was involved in a sustained duel with runner-up Madhmoon before Anthony Van Dyck swooped late.
It was a joint career-best effort on his third start on Racing Post Ratings and with the prospect of improvement to come he should prove to be a leading colt in the three-year-old division.
Anthony Van Dyck
The Derby winner has a head start on his O'Brien stablemates at the head of the BHA ratings before and after Epsom, and there are reasons to believe he could go higher.
His trainer has already broken the mould with his campaigning of some of his best horses and Anthony Van Dyck looks like he could be another who relishes being set some searching challenges.
Broome, Sir Dragonet and Japan are more unexposed but there is no guarantee they will improve massively and Anthony Van Dyck has been progressive for the step up to middle distances this year, having been no slouch over seven furlongs and a mile against some of the best last year.
Factor in his discomfort coming down and around Tattenham Corner and the fact he was isolated alone against the rail where he would not have seen his closing rivals, and there is a case for upgrading his bare form.
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