Don Cossack, only third in the Ryanair Chase at the Cheltenham Festival in March but then a Grade One winner on his next two outings, is the champion steeplechaser at both two-and-a-half and three miles plus in the official Anglo-Irish classifications for the 2014-15 season, which have been published.

Don Cossack has been rated 3lb ahead of Coneygree, the Cheltenham Gold Cup winner, in the staying chasers’ category with a rating of 175. Coneygree, who was the first novice since 1974 to win the Gold Cup when he beat Djakadam (170) by one-and-a-half lengths, is rated alongside Silviniaco Conti, the King George VI Chase winner, on 172, while Vautour, the brilliant winner of the JLT Novice Chase at Cheltenham, is one of six chasers rated 170 or above with a mark of 171.

The strong showing of novice chasers in the ratings confirms the growing impression during the season that the 2015-16 campaign could be one of the most exciting and competitive for many years at the highest level of steeplechasing.

Don Cossack’s rating is more than a stone behind the 190 allotted to Kauto Star at the end of the 2009-2010 season, but the wealth of up-and-coming talents rated within 6lb of the top offers a hint, at least, that an outstanding new crop of chasers is about to come of age. Don Poli (163), the RSA Novice Chase winner, is also expected to be aimed at the 2016 Gold Cup, and the current ante-post betting makes Vautour the favourite at 6-1 with Don Cossack, Coneygree and Don Poli next in the list at 7-1, 8-1 and 9-1 respectively.

“Don Cossack finished third in the Ryanair Chase [at Cheltenham] having made a mistake and being hampered two out at a very crucial time of the race,” Mark Olley, the handicapper responsible for two-and-a-half milers, said.

“Then he came out in the Melling Chase [at Aintree] and destroyed the field there. The hard thing about it was what on earth to call a 26-length win ahead of some reasonably solid horses? It was such a hard race to put a level on and strictly speaking it could have been a lot higher than 175, but we were weighing up whether all the others just underperformed. Then he came out and won again [over three miles] afterwards which helped to tie a level to the form.”

With three of the first four in the Gold Cup market about to embark on only their second season over fences, the amount of improvement each of them can find between now and Cheltenham could be decisive next March. Willie Mullins’s Vautour, the Supreme Novice Hurdle winner in 2014, will be attempting to win at the Festival for the third season running, and Noel O’Brien, Ireland’s senior handicapper, sees him as potentially the most significant rival for both Coneygree and Don Cossack.

“Don Cossack’s run at Cheltenham does raise the question about him at Cheltenham, and he fell there as a novice,” O’Brien said. “But away from Cheltenham, his form was absolutely rock-solid. At Aintree, we were downgrading all those behind him, but even then, 175 was going to be a minimum.

“On his debut, Vautour demolished a high-class field at Navan and in 30-odd years, I don’t remember seeing as impressive a performance in a beginners’ chase. It wasn’t that Cheltenham was the biggest surprise ever, Ruby [Walsh, his jockey] has said that he can go over any trip, and that’s how it has looked so far as well. Vautour is a genuine champion in his category.”

His British counterpart Phil Smith, however, was more sceptical about Vautour’s prospects over three-and-a-quarter miles at Cheltenham, even if he might prove to be the best chaser overall next season.

“I’m already anticipating next year’s Gold Cup,” Smith said. “Let’s hope and pray that they all get there OK, [but if they do] it’s a fantastic race because you know exactly how it’s going to pan out. Which of those pretenders to Coneygree’s title are going to have the guts and ability to mix it with him and still be staying on at the end?

“You’re going to need a grinder, and I have some doubts, for all the brilliance of Vautour whether he will take to that kind of race. It may be that this time next year, we’ll be sitting here next year saying Vautour is the best chaser around, but he didn’t win a Gold Cup.

“I see Denman [the 2008 Gold Cup winner] as a proper Gold Cup horse, gutsy-ing it out and slogging away. I think a host of these horses might come into the Gold Cup next year with fantastic form and very attractive in terms of what they’ve done, but the demands of a Gold Cup are so unique that they don’t quite run up to it.”

In the two-mile chasing division, Dodging Bullets, the winner of the Queen Mother Champion Chase at Cheltenham, was the champion with a rating of 171, but the novice Un De Sceaux, who took the Arkle Trophy over the same course and distance, is assessed as having just 3lb to find in order to match him when he steps into senior company next season.

“Few last year would have predicted Dodging Bullets as this year’s champion two-miler,” John de Moraville, the handicapper responsible for two-mile chasers, said. “He was fourth in the Arkle [Trophy at Cheltenham] and then tailed off at Aintree. But after finishing third [on his seasonal debut] he went from strength to strength in the Tingle Creek, Clarence House and then the Champion Chase.

“Sire De Grugy and Sprinter Sacre [the winners of the Champion Chase in 2014 and 2013] both failed to recover their best form and were both very disappointing at Cheltenham.”

Dodging Bullets achieved his highest rating in the Clarence House Chase at Ascot, when he beat Sprinter Sacre, who was running for the first time in 13 months after suffering an irregular heartbeat in a race at Kempton in December 2013. De Moraville, however, firmly believes Sprinter Sacre’s best days are now well behind him, even if he remains in training.

“He was a stone-and-a-half below where he was two seasons ago,” De Moraville said. “I think it’s very unlikely he’s going to scale those heights again.”

Un De Sceaux, by contrast, appears to have the division at his mercy. “I’d be very disappointed if Un De Sceaux isn’t the top-rated two-mile chaser next year,” Smith said, while O’Brien underlined the Arkle winner’s scope for improvement.

“He was possibly a Champion Hurdle-standard horse who was unbeaten in all his completed starts,” O’Brien said, “and when he did fall at Thurles [in November], he was a long way clear. He’s a very, very exciting horse, and while he didn’t quite replicate his form at Punchestown where it was felt beforehand that the ground was perhaps a little quick for him, he was superb at Cheltenham.”

Willie Mullins, Ireland’s champion trainer, dominated the Cheltenham Festival with a total of eight winners, and horses from his stable tower over the hurdles ratings in similar fashion. Faugheen, the unbeaten Champion Hurdle winner, is rated 174 in the two-mile division, 5lb clear of his stable companions Arctic Fire and Hurricane Fly, with Nigel Twiston-Davies’s The New One a distant fourth on a mark of 162.

Among novice hurdlers, Mullins is responsible for the champions at both two miles and two-and-a-half in Douvan (161), the Supreme Novice Hurdle winner, and Nichols Canyon (155) respectively, and Douvan is seen as the main obstacle to a second Champion Hurdle win for Faugheen.

The fact that so many of the best National Hunt prospects are stabled in the same yard was a point for debate among the handicappers, with Smith relatively unconcerned about Mullins’s current pre-eminence.

“Were we not saying exactly the same thing 15 or 20 years ago about Godolphin on the Flat?” Smith said. “People were saying we might as well all pack up and go home because they will win everything. But we weren’t saying two years ago that Paul Nicholls had no chance of being champion trainer again when Nicky Henderson had Sprinter Sacre, Bobs Worth and Simonsig. I think you do get years like this, but for me it’s quite cyclical. Who’s to say that in a few years’ time, those horses won’t be with a different trainer. These things happen in racing.

“Yes, he’s got some fantastic horses, and it’s great that we’re seeing them. As a racing enthusiast, it doesn’t fluster me that one yard is winning lots and lots of Grade Ones. It could be temporary, who’s to say, but at the moment, I think we should just enjoy fantastic horses running that we’re really excited by.”

O’Brien, meanwhile, suggested that it would be positive for Mullins’s domestic competitors to take him on a little more vigorously at times, and not be intimidated by sheer weight of numbers.

“Willie’s in a great position at the moment that he can enter maybe six or seven horses in a Grade One,” O’Brien said. “They’re not all going to run, but it often ends up with two or three runners in it and Willie’s wins. I think if you were Willie you’d do the same, he has that firepower [but] it’s interesting that when trainers have stuck the course and stayed in the race, they are competitive. Don Cossack [who beat Mullins’s Champagne Fever in the Kinloch Brae Chase in January] is a good example.

“I’m now looking at the Pattern [of Graded races] at home and I’m wondering if we don’t have too many. Is it good that we don’t get more clashes between the better horses, even from the same stables? If you have a Pattern that allows horses to cherry-pick, that’s what’s going to happen.”

Gleneagles, the 2,000 Guineas winner at Newmarket earlier this month, is odds-on to add the Irish equivalent to his record this weekend after 16 horses stood their ground for the Classic on Tuesday.

Aidan O’Brien’s colt is top-priced at just 4-9 to win at The Curragh on Saturday, with Richard Hannon’s Ivawood, third home at Newmarket, next in the betting at 5-1. Hannon’s Estidhkaar, however, will miss the race after scoping poorly on Tuesday morning, and will be replaced in the line-up by his stablemate Lexington Times, an outsider at 40-1.

Belardo, last season’s Dewhurst winner on rain-softened ground, has also been declared for the Classic by Roger Varian, his trainer.

“He doesn’t want [the ground] too quick,” Varian said on Tuesday. “I think good ground and anything easier than good is favourable. He did some very nice work on Sunday morning, the plan is to run him on Saturday and we just hope it doesn’t dry out too much. You have to keep faith in these horses and you can’t write them off after one run, especially as the ground was very quick at Newbury [when Belardo was beaten in the Greenham Stakes] and he just never let himself down.

“He didn’t have a hard race, he’s a fresh horse. His work had been excellent leading up to that race and excellent since. We’d be very confident that, provided the ground isn’t too quick, we’ve a very good horse on our hands still.”

Belardo is top-priced at 14-1 alongside Highland Reel, one of a total of seven entries from O’Brien’s stable, and it is 20-1 bar.