Smart sprinter Came From The Dark has been ruled out of the Qipco British Champions Sprint.
A Group Three at Sandown in July when taking the Coral Charge, the Ed Walker-trained gelding was a general 20-1 shot for Ascot next month.
However, Walker reports the five-year-old to be finished for the season after undergoing surgery on an injury.
He said: “He got injured in the Palace House, it was a strange injury. We did all sorts of diagnostics, he was lame after that race and we couldn’t find a thing.
“We eventually found a very small ligament injury in his hock, the vets did a tremendous job of getting him right – so much so he went to Sandown and won a Group Three there.
“Unfortunately it reoccurred after that race, so I’ve had to draw stumps with him. He’s had surgery and is out for the year.
“It’s frustrating because he was really getting it together this year and hopefully he’ll be around next year for a shot at some of those big five-furlong races.”
Stablemate Primo Bacio could drop in class for her next outing, with Walker eager to get her back on the winning trail.
The filly was beaten just two and a half lengths by triple Group One winner Alcohol Free on her first start of the campaign, when remarkably she was sent off a 100-1 shot in the Fred Darling at Newbury.
Primo Bacio then claimed a Listed race in eyecatching fashion at York, with subsequent Falmouth Stakes winner Snow Lantern back in third, but that form was reversed at Newmarket when she finished fifth.
The Awtaad filly has since been seventh in the Prix Rothschild at Deauville and disappointed when beating home just one rival in last month’s City of York Stakes, with Walker believing Primo Bacio was feeling the effects of a busy period.
He said: “I don’t know what happened at York, I think I messed up and over-faced her and under estimated how hard a race she had in the Falmouth and then the Rothschild.
“Those three tough races and then backing her up against the boys at York. She’s a very exuberant filly at home and showed all the signs of being fine, but we found nothing to explain her very lacklustre and unlike-her run at York.
“We’re just freshening her up now, but do I want to pitch her back into a Group One on the back of that? Probably not, really.
“I think the worst thing you can do with these horses is chase the tail – she’s only a Listed winner.
“She’s going to stick in training and I think she will be a very good filly next year. I don’t think there’s necessarily any need to be chasing a dream that she can potentially fulfil next year.
“I’d like to get her back winning – maybe find a Group Three somewhere for her to win.”