William Muir’s stable star will try to complete his fairytale rise on Saturday, after victories in the King Edward VII Stakes at Royal Ascot and the Great Voltigeur at York.

The Lambourn trainer’s ace will face the might of Ballydoyle, with Aidan O’Brien three-handed as he aims to win the Leger for a seventh time. Irish Derby hero Santiago heads his team, completed by Dawn Patrol and Mythical.

Joseph O’Brien’s Galileo Chrome and Sunchart, trained by Andy Slattery, are the other Irish-based runners.

Ed Walker has declared English King, but the Lingfield Derby Trial victor is more likely to go to France for Sunday’s Juddmonte Grand Prix de Paris at ParisLongchamp.

Walker told Sky Sports Racing: “We’ve declared for the St Leger – but the plan for a long time has been to head to France, and we’re still very much leaning that way.

“We’re just very concerned about travel arrangements and the changing world of Covid. With numbers increasing here, the last thing in the world we want is for France to slap a two-week quarantine on people coming from England to France and then we can’t go – so we’re just covering all angles.

“We have to decide finally by 8.30am tomorrow, so it basically gives us an extra day to see how the water lies. If everything is equal we’ll be going to Paris on Sunday.

“Tom (Marquand) is booked to ride in the Leger, because I told Frankie (Dettori) a few weeks ago we were very unlikely to run in the Leger – and as far as I understand, Frankie is riding Santiago.

“Frankie is already (set to be) in France to ride Stradivarius, so I think we’ve got everything covered. It’s a huge day for Bjorn (Nielsen, owner) with Stradivarius back over a mile and a half in the Prix Foy on his way to the Arc.

“I think English King is as good as I’ve had him all year, to be honest. I know he’s got doubters now but I’m not one and I’m hoping this weekend he’ll prove them all wrong.”

Hukum, winner of the Geoffrey Freer Stakes at Newbury, will bid to give his trainer Owen Burrows a first Classic triumph at Doncaster.

Berkshire Rocco, Mohican Heights, Subjectivist and Tyson Fury complete the dozen hopefuls.

The three withdrawals at the 48-hour final declaration stage were Max Vega, Tiger Moth and Believe In Love – due to run in the Park Hill Stakes at Doncaster on Thursday afternoon.

Richard Hannon’s unbeaten colt Chindit faces six opponents in the Group Two bet365 Champagne Stakes.

Among the Ascot Listed race winner’s rivals are the experienced pair of Broxi and Devious Company, as well as Owen Burrows’ Albasheer and Irish raider State Of Rest.

Two past winners of the Prix de la Foret – Limato and One Master – are among eight runners in the Group Two bet365 Park Stakes.

Wichita, runner-up in the 2000 Guineas, and Jersey Stakes scorer Molatham represent the Classic generation.

The Harbour Watch colt was a 40-1 shot when runner-up on his seasonal reappearance at Kempton in early June, but has made giant strides since and disputes favouritism with the Aidan O’Brien-trained Santiago for the season’s final Classic on Saturday.

Muir acknowledges success on Town Moor would be a huge achievement for his small team during a time when, more often than not, the top prizes go to the bigger yards.

He said: “There’s a great mood in the camp. We have seven staff riding out, three staff in the yard, the staff in the office and me. It’s a small team, and everyone is delighted.

“We have about 26 horses. We’re not a fashionable yard – everyone wants somebody younger and more fashionable. It’s just one of those things, but if this horse could go and win on Saturday it would be fantastic for the whole team and everyone around it.”

A surprise win in the King Edward VII Stakes at Royal Ascot was followed by a luckless run in the Derby at Epsom, since when Pyledriver has given weight and a sound beating to his rivals in the Great Voltigeur at York last month.

Muir revealed the colt’s owners have received “life-changing” offers to sell over the course of the summer, but have so far resisted all potential buyers for a horse who did not even meet his reserve of £10,000 when sent to the sales as a foal.

“Anybody can come into this game, go out with a relatively small amount of money and you can find these good horses. They’re hard to come by, but you can find them,” Muir added.

“The owners have turned down some big offers. If the offers had been accepted I don’t think he would have stayed in this country – places like Australia and Hong Kong wanted him really badly.

“If one person had owned him, you couldn’t have said no to the kind of offers we got – it was life-changing money – but there’s three of them, and they wanted to keep him.”

The Lambourn handler insists he could not be happier with his stable star as he completes preparations for a race that is part of the 2020 Qipco British Champions Series – and he is optimistic the son of unbeaten sprinter Harbour Watch will stay the distance of a mile and three-quarters.

“He’s in great order and has done all the work he needs to do. As long as he stays like this for the rest of the week, I couldn’t be taking him there in better shape,” said Muir.

“I’ve always been a glass-half-full kind of person – my glass is always overflowing, to be fair.

“I think he will stay and I think we’ve got a great chance, but it is a horse race. I thought we had a great chance in the Derby, and it all went wrong, but you shake yourself down and go again.”

Whatever happens this weekend, Muir already has his eyes on some other major races – both this year and next.

“He’ll go for the Champion Stakes at Ascot after Saturday, as long as the hose is fine. That will be his last run of the year, because we’re not going abroad – it’s too difficult with the Covid,” Muir added.

“Next year is mapped out already in my mind. You could start off at Newmarket in the Jockey Club Stakes, then you’d go Coronation Cup at Epsom, Hardwicke at Royal Ascot, the King George – and at the back-end of the season, if we’re out of this Covid, we could go for the Arc.”

Pyledriver was one of 15 horses left in the St Leger at Monday’s confirmation stage.

As well as Santiago, Aidan O’Brien may be represented by Dawn Patrol, Mythical and Tiger Moth – while his son Joseph could saddle the progressive Galileo Chrome.

Other leading hopes include the Owen Burrows-trained Hukum, Mark Johnston’s Subjectivist and Ed Walker’s English King.

The latter also has the option of running in the Grand Prix de Paris the following afternoon.

“He’s in great form and is all set to run somewhere this weekend,” said Walker.

“We’ll have a look at both races during the week, see what the ground is looking like and decide where we go.

“We’ll make a decision much closer to the time.”