<p>Racing Victoria has pulled the plug on Sir Delius's spring carnival campaign just days before the <a href="https://www.sportsbet.com.au/events/cox-plate">Cox Plate</a>, with the <a href="https://www.sportsbet.com.au/events/melbourne-cup">Melbourne Cup</a> favourite becoming the first major casualty of the sport's enhanced veterinary protocols.</p> <p>The Gai Waterhouse and Adrian Bott-trained galloper won't contest either the Cox Plate next week or the Melbourne Cup after imaging scans revealed what vets described as a "heightened risk of injury."</p> <p>It's a brutal blow for connections who shelled out $2.7 million to bring the five-year-old to Australia specifically for these races.</p> <h2>What the Scans Showed</h2> <p>Sir Delius underwent Racing Victoria's mandatory CT scans and came back with concerning results. The stable then opted for a more detailed PET scan at the University of Melbourne Equine Centre, hoping for better news.</p> <p>They didn't get it.</p> <p>An imaging panel of three veterinary specialists reviewed both sets of scans over 24 hours and remained unanimous that the horse shouldn't race <a href="https://www.sportsbet.com.au/events/spring-carnival">during the spring carnival</a>. Racing Victoria stewards had no choice but to stand him down.</p> <p>The governing body introduced these protocols in 2021 after Anthony Van Dyck died in the Melbourne Cup that year. Seven horses had died in the Cup over seven years before the mandatory scanning began. There have been zero deaths since.</p> <h2>From Turnbull Winner to Sidelined</h2> <p>The timing couldn't be worse. Sir Delius dominated the Group 1 Turnbull Stakes two weeks ago, overcoming a wide barrier draw to win like a genuine champion.</p> <p>Gai Waterhouse called it potentially a dream come true to win her first Cox Plate with the horse. Jockey Craig Williams said Sir Delius "owned the track" during trackwork at Flemington and described him as a "great horse" who delivered when the pressure was on.</p> <p>Williams had talked up the Melbourne Cup specifically, pointing out that carrying 55.5kg represented a rare opportunity that wouldn't come again.</p> <p>The performance had Sir Delius firming in markets for both the Cox Plate and Melbourne Cup. Those bets are now void.</p> <h2>Waterhouse-Bott's Big Investment</h2> <p>The stable purchased Sir Delius for $2.7 million from clients specifically to campaign him in Australia. He'd won three of four starts here, with each run suggesting he was improving.</p> <p>Waterhouse said after Turnbull that he'd put on condition, relaxed more, and that whatever race he contested, "they're going to have to beat him."</p> <p>Now those plans are completely shot. The horse won't race again during the carnival, with stewards providing connections with the key information behind their decision.</p> <h2>The Protocol in Action</h2> <p>This marks the first time Racing Victoria's enhanced protocols have prevented a genuine contender from racing in their feature events. The system is designed to catch potential issues before they become catastrophic injuries.</p> <p>The process works like this: all Cup horses get mandatory scans. If concerns appear, the stable can request more detailed PET scanning. An independent imaging panel then reviews everything and advises Racing Victoria vets whether the horse should race.</p> <p>In Sir Delius's case, even the more sophisticated PET scan couldn't clear him. The panel maintained their view about injury risk after reviewing all available data.</p> <h2>What It Means for the Markets</h2> <p>The Cox Plate and Melbourne Cup betting markets will need significant reshuffling without one of the genuine favourites in the mix</p> <p>Sir Delius was being discussed as a genuine threat in both races based purely on his Turnbull performance.</p> <p>Other stables targeting the double will benefit from one less elite competitor, though nobody in racing celebrates these situations. Trainers and owners understand the protocols exist for horse welfare, even when the timing hurts.</p> <p>The spring carnival continues, but without one of its most exciting prospects.</p>