Nicky Henderson, the trainer of the outstanding hurdler Constitution Hill, said on Thursday that his unbeaten stable star has undergone wind surgery in advance of his much-anticipated return to action in the Fighting Fifth Hurdle at Newcastle on 30 November.

In a post on X, Henderson reported that Constitution Hill had been one of the star attractions at a stable open day on Wednesday, adding: “Constitution Hill is in particularly good form. He is still on the burly side following his summer holiday, but his work is starting to build up for his intended reappearance in the Fighting Fifth. He has had a wind operation a few weeks ago, which we feel might help him.”

Constitution Hill has raced only once since April 2023, when he won the Christmas Hurdle at Kempton on 26 December in the middle of a disrupted and frustrating campaign. His horsebox was already well on the way to Newcastle when the Fighting Fifth was called off due to snow on the track, while he missed the chance to defend his Champion Hurdle crown at Cheltenham in March because of a respiratory problem. Subsequently Constitution Hill went into hospital with colic, which ruled out a possible run at Punchestown in late April.

The letters “WS” against a horse’s name, to show that it has undergone wind surgery since its most recent start, have become a familiar sight on racecards since the declaration of such operations was made compulsory in 2018.

However, there was little evidence of any wind issues as Constitution Hill was racking up eight straight wins, including seven in Grade One events, without ever coming under serious pressure. As a result, the news that Henderson felt that an operation would “help” his horse came as something of a surprise.

Wind operations ensure that a horse is respiring as efficiently as possible when it is at full gallop, and are normally carried out either on the larynx or the soft palate.

Henderson has an impressive record with horses that are running for the first time after wind surgery. The trainer has saddled 10 winners from 44 runners after an operation since the start of 2023, and shows a healthy level-stakes profit of 24.5 points with those runners, thanks mainly to the 28-1 success of Caribean Boy in a race at Cheltenham in April 2023.

Constitution Hill is a 2-1 favourite to regain the hurdling crown at Cheltenham in March, with Lossiemouth, last season’s Mares’ Hurdle winner, next in the list at 7-2 and the reigning champion, State Man, priced up at 5-1.

At Doncaster on Thursday, Charlie Appleby’s Desert Flower extended her unbeaten record to three races in the Group Two May Hill Stakes, showing an impressive turn of foot to grab the lead inside the final furlong and then hold off the challenge of Aidan O’Brien’s January.

Desert Flower is now likely to head for the Fillies’ Mile at Newmarket on Future Champions weekend in October, and was cut to around 12-1 for next season’s 1,000 Guineas.

“We’ll go for the Fillies’ Mile and see where we go from there,” Alex Merriam, Appleby’s assistant trainer, said, “but she’s a big, scopey filly so hopefully all she’s going to do is improve.”

Trust Trueshan to lift Cup

Five of the six runners in Friday’s Group Two Doncaster Cup are separated by just 3lb on Timeform ratings and while Sweet William, the runner-up in the Group One Goodwood Cup last time out, is a logical favourite, an early price of around 2-1 looks very thin in the circumstances.

Gregory has not progressed quite as expected this season while Point Lonsdale’s stamina seemed stretched by two miles at York last month so this further step up in trip is something of a gamble.

As a result, the veteran Trueshan (3.35) could be a better alternative at around 5-1 to repeat his win in this race last year. He was just over five lengths behind Sweet William at Goodwood but that was on good-to-firm going and this return to a longer trip and, above all, an easier surface could be just what ne needs.

Doncaster 1.50 Subsequent did well to chase down a front-runner from some way off a steady pace at Newmarket last month and eventually won with something to spare. That was his first attempt at this trip and he has a fine chance to follow up off just a 4lb higher mark.

Doncaster 2.25 The impeccably-bred Jonquil was just a short-head in front at the line on his racecourse debut at Sandown last month but it was an impressive success in many respects as he was caught in traffic two out. He is entitled to improve significantly for the experience and while his rivals have more runs in the book, Sir Michael Stoute took this race with a similar type in Sangarius six years ago.

Doncaster 3.00 A wide-open renewal of the Flying Childers, and while the market leaders Big Mojo, Aesterius and Magnum Force all have obvious claims, Coto De Caza has improved by the run to reach a similar level of form and may be a little overlooked in the market at around 8-1.

Salisbury 3.55 The valuable novice event at York in July in which Greydreambeliever made a successful debut has not produced a subsequent winner from five runners, but she posted a notably strong time for a debutant and has more scope for improvement than her main market rivals.

Doncaster 4.10 Cabrera pulled a long way clear of the third horse home when going down only narrowly on her handicap debut at Newmarket last month and though she is up 4lb without winning, Ed Bethell’s filly still looks some way ahead of her mark.