Magical Memory could have his sights lowered at Haydock on Saturday week before connections consider the Darley July Cup at Newmarket on July 15.
The five-year-old grey, trained by Charlie Hills, beat just one horse home in the Diamond Jubilee on Saturday, with no valid reason having risen to the surface for his display.
His performance was all the more perplexing as Magical Memory had run such a promising race on his seasonal return in the Duke of York Stakes in May.
Sam Hoskins, racing manager for his owners Kennet Valley Racing, said: "It was simply too bad to be true.
"We knew he had a poor draw and he was too keen early, but that isn't an excuse to be beaten at halfway like he was.
"It's puzzling. Charlie says nothing has shown up since and we're at a loss to explain it.
"He's still in the July Cup but we couldn't go straight there after that so we're looking at running him in a conditions race at Haydock on July 8.
"If he were to win that well then we could think about the July Cup again but we'd have to run again first.
"Whether he didn't let himself down on the very fast ground, I don't know, but he's still a good horse, as he showed at York.
"I think he just had an off-day."