View from connections ahead of Wednesday's Neptune Investment Management Great Voltigeur Stakes at York.
A second challenge for a Classic could become a lot more likely for Main Sequence if he can deliver in Wednesday's Neptune Investment Management Great Voltigeur Stakes at York.
This race is considered the leading trial for the Ladbrokes St Leger, with Lucarno in 2007 the most recent of 13 horses to have so far achieved the double.
Main Sequence's trainer David Lanigan is reluctant to commit him wholeheartedly to the Leger at this stage, but a good performance from the Investec Derby runner-up at York will surely force his hand.
The Niarchos family's colt, who won the Lingfield Derby Trial, was last seen when a rather unlucky-looking fourth in the Grand Prix de Paris on Bastille Day.
Lanigan said: "He's done well physically and he's improved an awful lot, I think, as he's stronger looking now.
"In his home work he's never been a sparkling workhorse - he just does what he has to do - but we're very happy with him.
"The Leger is an idea at the moment. We'll see how we get on at York, but it's by no means a certainty.
"We'll just take it one race at a time and go from there.
"You never know about the trip until they do it on the track, but I always felt he'd get a mile and a half.
"He's a horse that relaxes in his races and does everything fine. He's got the right temperament.
"After York I'll sit down with the Niarchos family and Alan Cooper (owners' racing manager) and we'll make more of a long-term plan then."
Sir Henry Cecil will be double-handed, with Thomas Chippendale and Noble Mission clashing for the second time.
The pair were split by just half a length when first and second in the King Edward VII Stakes at Royal Ascot, while Frankel's younger brother Noble Mission went on to thwart Encke by a nose in Goodwood's Gordon Stakes.
"The Great Voltigeur looks a very good race but I am looking forward to running Thomas Chippendale and Noble Mission," said Cecil.
"Thomas Chippendale is an improving colt and I will be disappointed if he does not run a really big race.
"We are going to run Noble Mission without a hood as he seems to be maturing and more settled now."
Barry Simpson, racing manager to Thomas Chippendale's owner Sir Robert Ogden, said: "Henry's very pleased with him and he's satisfied with his work.
"The horse has come out of the race extremely well.
"He's been working pretty well and we're looking forward to York.
"We're not concerned whatever surface he runs on. He has a good attitude and takes his racing well.
"We're pretty confident he'll stay the Leger trip.
"There's no reason why he shouldn't, anyway."
Godolphin are double-handed, too, again pitching in Encke as well as Energizer, who has been recruited after becoming the first ever German-trained Royal Ascot winner.
Racing manager Simon Crisford said: "Encke lacked a bit of experience at Goodwood and that really found him out on that particular racetrack.
"He's done well since that race and I think he'll give a really good account of himself.
"If he runs a decent race, then he's entitled to go to Town Moor.
"Energizer is an interesting new recruit.
"He won very well over a mile and a quarter at Royal Ascot and is in good form."Connections of Thought Worthy see Thomas Chippendale as potentially the biggest danger.
The John Gosden-trained colt finished third in the King Edward and was a creditable fourth in the Derby on his penultimate start.
Gosden said: "My fellow's form is obvious - it is in the book.
"There is a small, elite field and it is quite a tight race - you could make a case for quite a few.
"The most impressive of them all may be Thomas Chippendale."