©Healy Racing Photos
Bobs Worth, ante-post favourite for the Cheltenham Gold Cup, will miss Saturday's Argento Chase, according to trainer Nicky Henderson.
The Nicky Henderson-trained eight-year-old was found to be not quite 100 per cent following a routine check-up earlier in the week.
He will now contest the Gold Cup on March 15 without a prep run.
Henderson told Press Association Sport: "Bobs Worth is not going to be able to run on Saturday, which is very disappointing for everybody, including the owners.
"We very much wanted to run, but the good thing is it doesn't affect March in any way.
"We were just doing a routine check on Monday, which all the horses have before they run.
"There was something not quite right with him and it's just going the wrong way, rather than the right way.
"We were scoping him and there was a little something there.
"It's not wise to run at the weekend if he's not going to perform to his best.
"It wasn't crucial that he ran, but it was always the plan."
The Seven Barrows handler is unfazed by the prospect of sending Bobs Worth to the Gold Cup without the benefit of another run.
His magnificent victory in the Hennessy Gold Cup at Newbury in December was his first start since he was victorious in the RSA Chase at the Festival last March.
Henderson said: "I always felt the Denman Chase (Newbury, February 9) was too close to Cheltenham for him - he's that sort of horse.
"Circumstances have now forced to us to go without it (a Gold Cup prep run).
"He's a very straightforward horse, but it's disappointing more than anything else."
Tidal Bay's Cheltenham Festival preparations have met a hitch with the news that the horse is "odds-against" to make his intended prep-race at the same track this weekend.
Nicholls told Betfair.com that the horse "should be considered doubtful" to make the Argento Chase line-up.
"After working this morning, he came back slightly lame," he said.
"Myself and Clifford [Baker, head groom] have looked him over and the problem is hard to diagnose. It could be either an infection brewing in his off hind foot, and or he has pulled a small muscle, but we don't know at the moment.
"We will obviously monitor him in the next 24 hours, and then make a decision on his participation in the morning.
"It isn't a serious problem - and he may well yet run on Saturday - but I thought it was best to keep everyone informed.
"At this stage, though, I think it is odds-against him running at Cheltenham at the weekend."