Big Buck's lost his unbeaten run over hurdles when he was relegated into a narrow third by 66-1 outsider Knockara Beau and At Fishers Cross in the Cleeve Hurdle at Cheltenham.

On his return from 420 days on the sidelines due to a tendon injury, trainer Paul Nicholls admitted his hand was forced into introducing the 11-year-old back into competition on heavy ground as he continued his preparation for a fifth World Hurdle.

While former jockey Ruby Walsh would usually restrain Big Buck's until the final couple of flights, new pilot Sam Twiston-Davies boldly sent him on with more than a mile remaining and it was only on the run-in his exertions started to count as he was passed by Knockara Beau and At Fishers Cross to hit the line in third, a short head and three-quarters of a length adrift.

Sent off the 6-5 favourite here, the Andy Stewart-owned superstar was cut by World Hurdle sponsors Ladbrokes to 5-4 from 7-4 for his next assignment on March 15 and Nicholls was only positive when interviewed afterwards.

"I'm delighted with him, he travelled with all his old zest and jumped well, but he just got a little tired after the back of the last," he said.

"It's very testing ground and we could easily have taken him out and saved him for another day, but I was desperate to get a run into him before the World Hurdle.

"This was only the second time he'd been on grass since his injury, I wanted another racecourse gallop but the ground wouldn't allow it.

"That will improve him enormously. I'm thrilled, I would obviously have liked to have won, but that will put him bang on for his next run.

"I said to Sam to be positive on him and if he got tired, he got tired."

Twiston-Davies said: "I rode him as if he was 150 per cent ready and he just got tired in the last 150 yards, which is fair enough as he has been off for more than a year. Most of the others had the benefit of a couple of runs.

"He has always been ridden handy and he jumped brilliantly. It was a real buzz for me, and I promise you when he takes them on again in the World Hurdle he'll run a massive race. He felt very special, as we all know he is."

Stewart said: "Perhaps it was lack of fitness, or age has got to him, but we'll definitely be there on the Thursday (of the Festival)."

When Twiston-Davies took the bull by the horns on the back straight, he initially had his rivals toiling but turning for home they had managed to regroup and Boston Bob, Reve De Sivola and At Fishers Cross all scented victory.

Knockara Beau, who is the same age as Big Buck's but invariably discounted despite five placed efforts from 15 previous tries at the course, made his own unexpected play for glory and wrestled the lead from the champion with 50 yards remaining.

Winning jockey Jan Faltejsek said: "He has run some amazing races at Cheltenham and always just missed out, but he's finally won and I'm over the moon.

"In the past he has made little mistakes that have cost him so hopefully he has learned his lesson."

Knockara Beau's trainer, Northumberland-based George Charlton, said: "Even if he makes mistakes, he always goes well up that last hill, and you wish the winning line was at the top!

"We were fairly worried about the ground, but he'd had a little wind operation. He's been dropping his soft palate, he was hitting the fence coming down the hill.

"He had it done about three years ago and we've just had it done again. He didn't drop his soft palate today. The horse needed confidence which is why he ran over hurdles.

"The plan was to go for the Kelso race which he'll have 12st in next month but I've put him in the Gold Cup and I might just run him."

Rebecca Curtis can be more encouraged by At Fishers Cross, whose jumping still has not returned to last season's fluency but this was undoubtedly a step in the right direction.

"It seems like he's getting back to where he was last year," she said.

"He's had a lot of physical problems, but that was a lot better and we can think about coming back here now."