The racing roller coaster took a big dive at Royal Ascot on Day 4 which was not a good day for favourite backers with roughies ruling in both G1 races and a first season sire produced the winner of the juvenile feature on the card.

The Listed John Turkington Forestry Castletown Stakes (1200m) was one of the few age-group features in the lower North Island that was missing from Lisa Latta’s CV, but the fast-improving filly Platinum Diamond dealt to that unfinished business at Otaki on Friday.