Keith Melrose casts his expert eye over a high-quality Coronation Stakes field

2.25 AscotCoronation Stakes (Group 1) | 1m | 3yo fillies | ITV/SKY

There is normally three days of separation between the St James's Palace and its equivalent for fillies, the Coronation Stakes. As though to honour the occasion of the gap closing to 35 minutes for one year only, the Coronation has copied the form of its more celebrated sibling to an uncanny degree.

The favourite was beaten into third in the Guineas at Newmarket, losing her unblemished record in the process. She still heads the betting to gain revenge on the Guineas runner-up, with the major threat to the pair coming from a fast-improving John Gosden-trained runner who has never before run at Group 1 level.

Admittedly, the similarities end there. For a start, Pinatubo is more of a St James's Palace-type miler, whereas Quadrilateral would theoretically be better suited to a Guineas, which often tests stamina that little bit more with there being no mid-race bend. Quadrilateral's ability is not doubted; the main question is whether she should be in an Oaks trial instead.

She shaped better than Cloak Of Spirits at Newmarket, as the latter was let loose on the front and that probably made a head's worth of difference at the line. While Cloak Of Spirits is smart, having also been a close third in the Rockfel, her Group 1 class might be slightly overplayed by her Guineas second.

The Gosden runner is Run Wild, who actually won an Oaks trial last time. In pure form terms, it was only a small improvement on her juvenile form, but the manner was what impressed.

Watching the cruising speed she showed, you would imagine she would cope with a mile, but given she is a long-striding filly it is not a given, especially moving up to Group 1 company.

She is also bred to prove best beyond a mile. It is surmised that she is running in this race partly because stablemate Frankly Darling exists, which is not the same as saying she cannot win.

The three Irish runners – Alpine Star, So Wonderful and Love Locket – do not feel like exotic raiders given there is an American runner. Graham Motion has sent Sharing, who won on turf at the Breeders' Cup in November. She has a European manner of racing, not the eyeballs-out style familiar in her homeland, and those who keep an eye on US workouts suggest she is being trained that way.

There is a European link to Sharing's form. At the Breeders' Cup she beat Daahyeh, who had won the Rockfel (Cloak Of Spirits third) and been second to 1,000 Guineas winner Love in the Moyglare.

It could be argued that run alone makes her value at around 6-1 and doubts over the surface are quelled by her sire, Speightstown, having produced a reasonable number of classy European turf horses, few of whom were reliant on fast ground.

Keith Melrose, betting editor

Roger Charlton: Quadrilateral needs to settle

Roger Charlton was pleased with Quadrilateral's third in the 1,000 Guineas but admits she must settle better if she is to make an impression against a high-quality field in the Coronation Stakes.

The daughter of Frankel, who was undefeated as a two-year-old, finished behind Cloak Of Spirits and Love in the Classic this month after racing keenly in the opening stages under Jason Watson.

"She seems to have come out of the Guineas very well," said Charlton. "Having a hard race 13 days earlier is hardly an ideal prep but there are no rules in this business and we won't know until we try.

"She appeared to be a bit keen going to post last time and was too keen for probably five of the eight furlongs, but having done that she did incredibly well to stay on for third. She really needs to settle.

"We'll learn a lot, including how she goes on softer ground. We're also going without a tongue-tie, which perhaps made her a bit keen last time. We hope she runs well but this looks like a strong race."

Charlton believes a mile and a quarter will be within her grasp but decided to go for the Coronation Stakes rather than wait for the Prix de Diane, which would be complicated by travel and quarantine arrangements.

"We've not really got a target for her after this. It's a concertinaed programme book but there are races about. She'll probably stay at eight or ten furlongs, rather than suddenly spring into the Oaks."

What they say

Jessica Harrington, trainer of Alpine Star
She'll love the ground. She likes a bit of dig in it. She hasn't run for a long time but I couldn't be happier with her. She's in very good form and we're looking forward to running her.

Richard Hannon, trainer of Cloak Of Spirits
We just have to assume she’s fine. She looks fine, she’s moving fine, that’s all you can base it on. Hopefully the track will suit her. She’ll prefer Ascot round a bend much more than Newmarket.

Aidan O'Brien, trainer of Love Locket and So Wonderful
They're in good form. The drier the ground, the better it will suit them. Love Locket won nicely at Leopardstown and So Wonderful ran well in the Irish 1,000 Guineas. They're coming back quick, though, so we'll see. They seem to be in good form.

John Gosden, trainer of Run Wild
We're hopeful she'll handle the ground as she ran well on testing conditions at Deauville last year. She's coming back in trip but deserves to take her chance.

Graham Motion, trainer of Sharing
I'm comfortable with her going over a mile but she may want further in time. We decided to keep it straightforward and run her against three-year-old fillies rather than in open company. My main worry is the rain as it would be a different challenge in testing conditions.

Read more:

Aidan O'Brien weighs up Classic plans for Guineas winners Love and Peaceful

Royal Ascot day five: confirmed runners and riders as Pinatubo faces six

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