Future plans are on hold for Nostrum after the exciting colt finished lame when hot favourite for the Strensall Stakes at York on Saturday.

Third behind fellow Juddmonte-owned three-year-old Chaldean in the Dewhurst at Newmarket last term, the son of Kingman missed the first part of the current campaign after suffering a setback in the spring.

A spectacular comeback win in a Listed race at Newmarket last month suggested Sir Michael Stoute’s inmate was destined for the top, but he was beaten by Epictetus in the Thoroughbred Stakes at Goodwood and trailed home last of six runners in another Group Three on the Knavesmire on Saturday.

Whether Nostrum runs again this season remains to be seen, with connections still trying to discover the exact cause of his disappointing performance.

“He was lame behind on the day and it will be investigated a bit more today and tomorrow,” said Juddmonte’s racing manager Barry Mahon on Monday.

“I don’t think it’s anything too sinister from what Sir Michael was saying, he thought it might have been more muscular than anything, but until we check it out we’ll wait and see.

“We won’t know what the plan is until we get all the results back and see what was causing the niggle.

“It was disappointing, but it would be worse if there was no reason for it. The main thing is getting him right as we know the talent is there and the ability is there, it’s just about getting him right.”

A Juddmonte runner who produced a more positive performance at York was Bluestocking, who was beaten just three and a half lengths into fourth place in Thursday’s Yorkshire Oaks.

Ralph Beckett’s filly has previously finished third in the Ribblesdale Stakes at Royal Ascot before being narrowly denied by Savethelastdance in the Irish Oaks, and her team must now decide whether to lower her sights or line up in another Group One contest on Qipco Champions Day at Ascot.

Mahon added: “I thought she ran a lovely race and she’s a filly that’s probably still a little bit on the weak side when you watch her going round the ring compared to some of the opposition.

“I thought it was noticeable that there’s still a little bit of weakness in her and I think she’s filly that will be better next year, but she’s running to a high level of form.

“A little bit more ease in the ground probably suits her a little better and I’m sure there’ll be good days to be had with her along the way.

“We haven’t really decided where we go next, we need to discuss that with the owners. We touched on it after the race whether we drop in class and win a race this year or she goes to the fillies’ race on Ascot on Champions Day.

“We’ll let her get over York and speak with the owners and then decide in the coming weeks.”

Mahon also provided an update on 2000 Guineas hero Chaldean, who has enjoyed a mid-season break since failing to fire in the Prix Jean Prat at Deauville in early July.

The Andrew Balding-trained son of Frankel is being readied for the Queen Elizabeth II Stakes at Ascot on Champions Day, with a prep run at Newmarket in the pipeline.

“I think Andrew in the back of his head is slightly thinking of the Joel Stakes,” said Mahon.

“He’s back in Kingsclere and cantering away and we sort of said we’d just monitor and see how he goes closer to the time, but Andrew was thinking Joel Stakes and then the QEII.”