David Lanigan’s stable star has already taken on Aidan O’Brien’s unbeaten colt once before in the Investec Derby at Epsom in June when he stayed on well to take second place, five lengths behind the brilliant winner.
But while the 2000 Guineas hero has gone on to further Classic glory in the Irish Derby at the Curragh, Main Sequence has suffered defeat in both his subsequent races.
An unlucky fourth behind Camelot’s stablemate Imperial Monarch in the Grand Prix de Paris at Longchamp in July, Main Sequence was second behind Thought Worthy in the Great Voltigeur Stakes at York last week.
The Lanigan team are toying between whether to step Main Sequence up to an extended mile and three-quarters in the world’s oldest Classic on September 15, or to return to Longchamp for the Prix Niel a day later.
“He’s come out of the race fine, but I still have to sit down with the owners and decide which way we’re going with him,” said Lanigan.
“He’s in the Irish Champion Stakes, but he won’t run there.
“The two options for him are the St Leger and the Prix Niel in France.
“I need to discuss things with the owners and then make a final decision.”
Camelot heads the 16 remaining entries for the St Leger at the latest scratchings stage as the build-up continues to his bid to become the first horse since Nijinsky in 1970 to complete the Classic hat-trick on Town Moor.
Camelot is one of six remaining possible runners for the powerful Ballydoyle team, with Imperial Monarch, Chamonix, David Livingston, Father Of Science and Offer.
John Gosden has a well-documented strong hand, with the Clarehaven maestro responsible for five possible runners.
Thought Worthy could be joined by Irish Oaks heroine Great Heavens, Shantaram, Michelangelo and Dartford.
Thought Worthy is owned by George Strawbridge, whose his racing manager James Wigan, said: “I would say Thought Worthy is a likely runner in the St Leger.
“He put in a very gutsy performance in the Great Voltigeur Stakes last week when he really put his head down and tried.
“Dynaformers have a habit of improving.
“Thought Worthy is a lovely looking individual and physically he has come on significantly since his run at Royal Ascot.
“His brother Lucarno won the St Leger and Thought Worthy really tries and gallops so you never know.”
Hugely impressive Melrose Stakes winner Guarantee could become a first Leger runner for trainer William Haggas, while Encke, Thomas Chippendale and Ursa Major complete the high-class list.
Meanwhile Premio Loco is likely to have just one more run this season following his game victory in the Celebration Mile at Goodwood on Saturday.
The Joel Stakes at Newmarket next month, in which he finished second last term, is the race trainer Chris Wall is considering for the eight-year-old who has now won five Group Two races.
Wall is hoping the Prized gelding can retain his form for another year at least and plans to prepare him for the 2013 Winter Derby at Lingfield which he won in March.
“He’s done very well over the years and has been a little superstar for us. He’s got a pretty consistent record at that level,” said the Newmarket handler.
“As he’s got a bit older I’m not sure he has the speed for seven furlongs now. We’ll be looking at races like the Joel Stakes at Newmarket as long as the weather doesn’t intervene and the ground gets too soft for him.
“That would be it for the season. We haven’t got any sexy entries overseas for him.
“He’s already had quite a long year and we want to look after the old boy.
“It’s one more run hopefully for him this year and then bring him back for next year.”