Inglis Drever became the latest high-profile casualty of the New Year when he was ruled out for the rest of the season with a tendon injury.
Three leading Cheltenham Festival candidates have now been sidelined in as many days, with Harchibald and Kicking King also suffering setbacks.
"He is out as he has injured a tendon," owner Graham Wylie said.
The seven-year-old scored at Wetherby on his seasonal bow and then landed the Ballymore Properties Long Distance Hurdle at Newbury in November. It is thought he picked up the injury around the time of his second run and that may account for his fall when already looking beaten in the totesport Long Walk Hurdle at Chepstow.
"He has had a lot of hard races and the problem might have surfaced after New-bury," Wylie continued. "That would explain why he wasn't travelling very well in the Chepstow race and that run could have aggravated it.
"He seemed fine apart from a little bit of swelling, which we thought was nothing more than bruising.
"If we had ignored it and carried on it might have made it worse, so we have done what is best for the horse and hopefully he will be back for next season."
Wylie's No Refuge had already been prominent in the betting for the Cheltenham stayers' contest and the Royal & SunAlliance Hurdle winner is now poised to take over the mantle from his stablemate.
"No Refuge would have to come into the picture now," added Wylie. "We wanted to try him at three miles and he was there in case something happened to 'Drever'."
County Durham-based Johnson said: "He had that fall at Chepstow and he was sound enough when he came home, but he had been lame at the track.
"We nursed him for a week and he did some swimming. I gave him a walk out and a jog and I wasn't 110 per cent happy, so I called the vet in. He scanned him and behind the knee there is a black hole, which tells you enough is enough for the season. It is like Tim Forster used to say 'you are not just a little bit pregnant'.
"He won't be ridden out again this season and we will make a decision on whether he has to be fired or just left for mother nature."
Johnson's charge lowered Baracouda's colours at Cheltenham last March and handed out another beating in the Newbury race. The Francois Doumen-trained runner is now the 4-1 cofavourite with Coral alongside No Refuge and Rhinestone Cowboy.
Jonjo O'Neill's Rhinestone Cowboy, winner of the Bally-more Properties Champion Stayers Hurdle at Punches-town in 2004 but unraced since, is William Hill's new 4-1 favourite, with Baracouda next best at 9-2. Ladbrokes are even more cautious about O'Neill's charge and make him their 3-1 market leader.