John Gosden admits as he wants to give him a fifth success at the William Hill St 26, Logician faces a step into unknown territory. It’s 23 years since the world’s oldest Vintage was first acquired by the master of Clarehaven with Shantou. He has added to his tally with three wins in five decades courtesy of Lucarno (2007), Arctic Cosmos (2010) Masked Marvel (2011). The Khalid Abdullah-owned Logician produced his debut only but made a big impression at winning his first few starts – with a prominent display being sandwiched by a pair of wins at Newbury . Frankel’s son graduated to Group Two class having a victory in the Great Voltigeur at York a month also will line up at Doncaster on Saturday as a favourite in the palms of jockey Frankie Dettori. “He has been in wonderful form since York. He’s very much a work in progress and did not start racing until late in life,” said Gosden. “I believed back May he might be a Leger horse. He even won a maiden down at Newbury, then a rookie above a mile and a quarter in the July route and then a 0-90 disability back at Newbury, when it was the first time he was ridden by Frankie. He’s come a very long way in a brief moment. “He stepped up again at the Great Voltigeur, and we’re really satisfied with him. “He is fine in addition to the ground, there is no doubt he is a better horse on good, easy side of great, but that might go for a few others.” Gosden believes the choice not to operate Logician as a two-year-old and give him a while to mature continues to be crucial. He said:”He came to us quite late, and that I believe giving him this time has profited him. “He’s a nice horse to be around. He contains a stride and is a very relaxed character. “I think the nice, long right at Doncaster must suit him well.” Both clear questions hanging over Logician going into the Town Moor showpiece are whether his shortage of big-race encounter could prove his undoing, and if his stamina will continue out over the one-mile-six-furlong distance. Assessing both facets, Gosden added:”We’ve been lucky to acquire the Leger four occasions, and those horses were seasoned than him. It is a evaluation of a thoroughbred on that trip – the 185 yards could be telling, and that the one-mile-six is some thing. “You always know you going into uncharted territories with a youthful horse like him. It isn’t like he has acquired a trial over a mile and three-quarters. “He offers me the indications, as he is really relaxed, he will stay ” As always, Gosden is respectful of the resistance – giving special reference to the Mark Johnston-trained Sir Ron Priestley, who claimed his fifth win from six starts this year in last month’s March Stakes at Goodwood. He explained:”I think it’s a good renewal. You own a horse in there who remained also and won the March Stakes. That has been a race I saw carefully, because we were second inside (together with Promissory). “It will probably be an end-to-end gallop, which is not a bad thing as it thins out the field. “You’ll get trouble in conducting, and I remember a few horses which have been unfortunate not to win there. I shall leave all that to the horse and Frankie – . “When you see the horses which are still rolling between the two-furlong mark and also the one, that will tell us what sort of quality Leger it is.” Dragon to fire Il Paradiso and sir Dragonet provide a hand that is solid to Aidan O’Brien. The Ballydoyle handler claimed his sixth victory from the Town Moor showpiece with Kew Gardens 12 months past – including to his previous triumphs with Milan (2001), Brian Boru (2003), Scorpion (2005), Major Lighting (2013) and Capri (2017). Chester Vase winner Sir Dragonet has had this season tilts Classic glory , completing a close-up fifth when preferred in June for its Investec Derby at Epsom. He was defeated at odds-on on his return from a midsummer fracture at the Royal Whip Stakes at the Curragh last month, however, O’Brien believes his bill will likely strip much fitter on Saturday – and is confident the measure up to a mile and also three-quarters will not be an problem. Assessing the main market equal to the John Gosden-trained Logician, O’Brien said:”Sir Dragonet is a horse that has lots of class. “He was just ready to return at the Curragh. He received a bit tired, which he had been entitled to perform. I was being very attentive and gentle with him. “He’s never run anything under a mile and a half an hour, aside from the previous day over a mile and a quarter. He was started by us and we think there is a great chance. “I really don’t believe he’s earth dependent. He ran before Epsom on ground, and that was good ground, and he also came out of that ideal. “There is no doubt his very best run was that his Epsom run” Sir Dragonet’s stablemate Il Paradiso has proved his stamina, having produced a career-best performance when behind celebrity stayer Stradivarius at the Lonsdale Cup a month more than two miles at York. “He stays very well and looks like a horse which will find a Gold Cup excursion – he seems like he will get two and a half kilometers,” O’Brien added. “I believe he will be happy enough. He does not mind being ridden. You’d be riding him like you’re positive he will remain and the other (Sir Dragonet) you’ll be taking time with a bit, I would imagine.” O’Brien also saddles rank outsider Western Australia. Sir Ron Priestley has won five of his six starts this season – his blip. Mark Johnston’s charge is unbeaten in 3 following appearances and steps up to Group 1 level for the first time. Johnston, who has a second string to his bow Nayef Road, said:”He (Sir Ron Priestley) has got a lot to locate, and it would have to be a career-best, however, he wants to be present. “He’s done almost everything right from the lower doses, with the exception of Royal Ascot. Today he has got to step up to the huge one. “I never dismiss the Leger, since I have run some top horses in it and they’ve been defeated. We know he gets the trip, therefore we don’t have any doubts about him . “Many of these in there will be receiving the trip they are course horses, so that they need to do. He remains the trip very well and is a genuine horse” Martyn Meade’s Geoffrey Freer winner Technician and Dashing Willoughby, from Andrew Balding’s yard, complete the field. Balding said of his Royal Ascot winner:”He has run well at Newmarket on Goodwood on fast ground so he doesn’t have to get it soft. “He’s run into a fair level all year and been really consistent, so I’d expect he would run well.” Read more: