Altior 1-8 for Clarence House after Mullins elects to keep Un De Sceaux at home

Altior will go off as one of the shortest favourites for a Grade 1 in Britain and Ireland in the last 20 years after main rival Un De Sceaux failed to feature among Thursday's declarations for Saturday's Matchbook Clarence House Chase at Ascot.

Already a 1-4 shot to win a 12th straight race over fences, Altior's price contracted to 1-8 following the news last year's winner of the race would not be back to defend his crown for Willie Mullins.

Explaining the decision, Mullins said: "We decided not to declare him as he needs slower ground at this stage of his career. He's in very good form and he has a very good record at Ascot, but he owes us nothing and we'll wait until the ground eases before running him."

The omission of Un De Sceaux means Altior will face just Diego Du Charmil and Fox Norton, and his starting price is likely to be the shortest in Britain for a Grade 1 since Sprinter Sacre returned a 1-7 winner of the 2012 Maghull Novices' Chase at Aintree.

But there will need to be either another withdrawal or some industrial strength bets for Altior's price to reach 1-16, the price Hurricane Fly was when winning the 2013 Morgiana Hurdle at Punchestown.

Three short-priced stories

Istabraq, Hatton's Grace Hurdle, Fairyhouse, 1999
Three-time Champion Hurdle winner Istabraq was expected to dot up in his bid for a third Hatton's Grace, but punters did not reckon on the tremendously tough Limestone Lad, who made all and held off the 1-7 shot.

Hurricane Fly, Morgiana Hurdle, Punchestown, 2013
A 1-16 chance to win a 17th Grade 1, Hurricane Fly obliged, but anyone who had taken short prices would have been a bit anxious approaching the finish as the brilliant hurdler needed the run on his seasonal reappearance, only defeating stablemate Marito by a length and a quarter.

Sprinter Sacre, Champion Chase, Punchestown, 2013
Before Altior, Nicky Henderson had another two-mile chaser who wowed racegoers, and while this was not his flashiest performance, his starting price of 1-9 was the shortest he returned in his outstanding career.

Being sent off odds-on is nothing new to Altior, whose longest starting price over fences was evens in last season's Champion Chase at the Cheltenham Festival.

Altior's shortest SP came in the Grade 2 Wayward Lad Novices' Chase in 2016 when he was a 1-9 chance, and it is possible he could go off even shorter for Saturday's Grade 1.

Ascot director of communications Nick Smith was not overly disappointed by the final field, and said: "Although we would have liked to have seen Un De Sceaux travel over you've got to be respectful of the decision.

"If you have a horse as dominant as Altior the net result is you will probably have a very small field. Fox Norton provides an interesting subtext and you don't get a superstar like Altior every year."

Robbie Power will be aboard the Colin Tizzard-trained Fox Norton, who will be having has his first start since being pulled up in the 2017 King George VI at Kempton. Harry Cobden will partner Diego Du Charmil with Nico de Boinville on Altior.

The ground at Ascot was good to soft on Thursday. The forecast is for 2-3mm of rain from Friday evening through to Saturday.

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