• Sky Bet odds: 15/8
• Timeform master rating: 119
• Form: -32122
• Sire: Galileo
• Biggest win: Group 2 Queen’s Vase

Pros: Sizeable sort who showed potential in spades in just two juvenile starts, placed behind Los Angeles at Group 1 level, and has steadily found his feet upped in trip as a three-year-old. Still showing signs of greenness when second to Ambiente Friendly in the Lingfield Derby Trial and the decision to skip Epsom paid off when winning with a bit to spare in the Queen’s Vase at Royal Ascot.

Comfortably held in the Grand Prix de Paris the following month but he boxed on bravely behind leading Arc hope Sosie and appeared to take his form up to new levels when defying a penalty in the Sky Bet Great Voltigeur at York last week.

Stays the Leger trip, handles all sorts of ground and looks about as dependable as they come, while to top it all off his form – being rated 119 by Timeform – will be the best in the field providing Los Angeles goes elsewhere as expected. Also likely to be the mount of Ryan Moore if that’s the case.

Cons: The market has all the above positives just about covered at a general price of 5/2 and, as a counter point, he is 0-2 in Group 1 company at this stage so, in spite of his obvious consistency this year, it would be hard to argue he’s a superstar middle-distance performer.

That’s borne out by the ratings, Timeform having Grosvenor Square just 1lb lower than Illinois and Jan Brueghel only 3lb behind, plus the ‘p’ for likelihood of further improvement to come from the latter.

• Sky Bet odds: 4/1
• Timeform master rating: 116p
• Form: 111
• Biggest win: Group 3 Gordon Stakes
• Sire: Galileo

Pros: Who doesn’t like an unbeaten, late-maturing Galileo colt going for Classic glory? It has been a case of steady improvement at every checkpoint so far for this one and his strong-finishing 10-furlong win from Trustyourinstinct at the Curragh in June worked out well with the runner-up second again to smart older horse (and last year’s Leger winner) Continuous in the Royal Whip.

He appeared to get a bit excited and stewed up in the preliminaries ahead of the Gordon Stakes, nothing new for Galileo progeny it must be said, but he again showed a tenacious attitude (ditto the observation regarding his late, great sire) to tough it out from Bellum Justum, who was in receipt of 3lb.

Goodwood was a fittingly glorious landscape for Jan Brueghel to really come to prominence and, while still untapped at this point, his stamina for the St Leger trip looks as close to guaranteed as you can get without yet having it in black and white of the form book.

Cons: Boiling over prior to a first shot at a new trip wouldn’t be far from ideal if it happens again at Doncaster and he’ll surely want to conserve a little more energy pre-race if he’s going to make it four from four in the Town Moor Classic.

It probably wasn’t the strongest edition of the Gordon, a recognised trial that hasn’t been won by a subsequent St Leger winner since Conduit in 2008 (nine horses have done the double down the years). The past two Gordon winners have been placed at Doncaster on their next start, though, and perhaps Jan Breughel will be the latest forced to settle for a supporting role.

• Sky Bet odds: 5/1
• Timeform master rating: 118
• Form: 1-3721
• Biggest win: Group 3 Irish St. Leger Trial Stakes
• Sire: Galileo

Pros: Here’s the one with cast-iron staying power having already had the two goes over a mile and three-quarters, chasing home the classy (Melbourne Cup-bound) Tower Of London in the Curragh Cup before his 20-length demolition job in the Irish Leger Trial back at the Curragh earlier this month.

Sent out into a clear lead on both occasions, nothing got near to him last time and he must possess a considerable engine at Ryan Moore claimed post-race that he still had plenty left in the tank.

Having won a Group 3 event on heavy ground at two and seemingly going from strength to strength as he’s gone up in trip, he could be extremely dangerous especially if there’s plenty of rain around come the middle of next month.

Cons: He does hold an entry in the Irish St. Leger and having won the main trial for that Group 1, there may be reasons to believe he’s perhaps a little more likely to take up that engagement than Los Angeles, Illinois and Jan Brueghel, who are also all entered at the Curragh.

Grosvenor Square doesn’t possess the same sort of mile and a half class as Illinois and his front-running tactics (almost bound to be used once more given the likely nature of the field) could set things up for his better-fancied stablemates.

• Sky Bet odds: 12/1
• Timeform master rating: 121p
• Form: 1-1311
• Biggest win: Group 1 Irish Derby
• Sire: Camelot

Pros: Fine-looking colt who was an unbeaten Group 1 winner at two and built on his Leopardstown comeback win when third to City Of Troy in the Derby at Epsom. Showed plenty of grit when back to winning ways in the Irish version at the Curragh and put in a classy, strong-staying performance to beat Illinois narrowly under a penalty in the Voltigeur at York.

Cons: Is he going to run? That would seem like an obvious stumbling block and obviously goes a long way to explaining his current odds as he’d be favourite if connections had come out and claimed Doncaster was his big end-of-season target. Instead it looks like the Irish Champions Stakes prior to a crack at the Arc is preferred and he wouldn’t be a shock winner of the Longchamp feature if there’s some ease underfoot. Not a betting proposition for the St Leger, though.

Conclusion

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Illinois came away from the Great Voltigeur with his reputation (and Leger claims) not only intact but enhanced, following the neck second to Irish Derby winner Los Angeles, and you’d be hard pressed to suggest he shouldn’t be favourite for Doncaster given the York winner looks like staying at home before a possible trip to Longchamp.

The unbeaten Goodwood winner Jan Brueghel and stout-staying GROSVENOR SQUARE do provide plenty of intrigue, though, and the latter looks a fascinating one at the odds following his runaway win at the Curragh (replay below). In fact, his past two races have been in another league compared to his limp effort in the Irish Derby and it just looks like he’s wanted a proper test of stamina all along.

Soft ground would be preferable, given his Group 3 juvenile win came on heavy going at Leopardstown in October, but if he’s granted a reasonably easy time of things out in front then he could be a hard horse to peg back no matter the weather.

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