Proud owner Andy Stewart insists Big Buck's remains at the top of his game at the age of 11 and expects him to fight all the way in an attempt to regain his stayers' crown at Cheltenham.
Big Buck's was the undisputed number one in the three-mile division with four Ladbrokes World Hurdles among a string of 18 successive victories from January 2009 to December 2012, until injury intervened and he was unable to defend his title last year.
Although beaten on his comeback run in the Cleeve Hurdle in January, the Paul Nicholls-trained gelding went down with all guns blazing in third behind Knockara Beau.
Everything has gone to plan since then, and Stewart is looking forward to facing the Willie Mullins-trained Annie Power, who has replaced Big Buck's as favourite and takes a 100 per cent record into the race.
Stewart said: "We massively respect the mare. She's unbeaten, but there are question marks over whether she will stay and if Big Buck's is back to his top form is she good enough?
"We think Big Buck's is back to his top form, but, just like his owner, he's getting on in age. He's done nothing wrong at all with his preparation since he was beaten three-quarters of a length in the Cleeve. If he had won by that margin, he would not be 3-1.
"I spoke to Alex Ferguson and he said if a player had been off for 42 days he would start him off in the reserves and not play him for the full 90 minutes until he'd had three or four games.
"With Big Buck's there was nothing else you could do but put him in a competitive race over three miles giving a bit of weight (8lb) to the winner (Knockara Beau), and he'd been off for 420 days plus it only the second time he'd been on turf.
"We are a little nervous, but there's nothing he's doing at home to suggest he's 11 years of age and he's had too much."
While delighted with Big Buck's, Nicholls admits he cannot sure if he is as good as he was.
"He'll love the ground, but he's 11 now and, as we saw with Hurricane Fly in the Champion Hurdle, can they be what they were?" he told Channel 4 Racing.
"How you see him (on Thursday) is what he is. I can't get him any better. I'm not saying he's better than he was before. The only way we will know is when he runs tomorrow, but I'm really looking forward to running him."
Sam Twiston-Davies rode Big Buck's for the first time in the Cleeve and is confident of a big run.
He said: "He must go there with a great chance. He's improved to suggest he could win a fifth."
Stewart's colours will also be carried by Celestial Halo, who was an admirable deputy for Big Buck's 12 months ago when second to Solwhit.
Stewart said: "On his comeback at Haydock, he needed the race. He'd had a foot infection which stopped him running at Ascot in the Long Walk so he'd had a bit of a lay-off as well. He's got a touch of class."
He is also represented by Salubrious, who is owned jointly by the Johnson and Stewart families.
"Salubrious is an improving horse and we should probably have run him in the National Spirit Hurdle at Fontwell," said Stewart.
"Like most of the horses in the race, he has got to massively improve to trouble a horse like Big Buck's, (but) I think he will run a big race."
Nicholls is mob-handed as he has a fourth runner in Zarkandar.
"It is just that we have no middle-distance hurdle race - two and a half miles - like they have at Aintree," said the Ditcheat handler.
"But there will be a good gallop whatever happens - it certainly won't be lacking in pace, that's for sure.
"Big Buck's needs a test of stamina, Celestial Halo needs a test of stamina and actually Salubrious, who I think will run really tidily, needs a test of stamina and a fast-run race. You don't really get a lack of pace in this race and if there is it won't be a problem.
"Celestial Halo stays, Zarkandar we're going to run to see if he stays, Salubrious I've got no doubt stays - he ran very well in the Long Walk - and he hasn't had his ground yet. He's in seriously good order and he's a big each-way price.
"Annie Power on reputation - no-one knows if she stays - is the one to beat. She won over two miles at Doncaster last time, but that doesn't tell us anything other than she was fit and healthy."