Proscenium Arch and Bonheur will attempt to give Trent Busuttin and Natalie Young a second win in the Thousand Guineas Prelude at Caulfield.

Two of the five most expensive yearlings sold in Australia last year among Sires’ field.

The Trent Busuttin and Natalie Young stable will await the return run of Equivocal before committing to a Blue Diamond start.

Trent Busuttin and Natalie Young to debut filly Bonheur at Caufield with the Blue Diamond in mind.