Johnny Murtagh is likely to team up with Ursa Major as he seeks to win the Ladbrokes St Leger for the first time at Doncaster on Saturday.

The Irish jockey is set to get the leg up on the Tommy Carmody-trained colt after connections confirmed plans to go for the world's oldest Classic.

The son of Galileo also holds an entry in the Gain Horse Feeds Irish St Leger at the Curragh the same day, but owner Andrew Tinkler will instead rely on Royal Diamond in that particular contest.

"We've made the decision to head for Doncaster (with Ursa Major) and let him take his chance against his own age group," said Tinkler's racing manager, Tim Jones.

"He's done absolutely nothing wrong up until now and appears to be very progressive.

"He did his final piece of work this morning in advance of the weekend. It all went very well, so it's all systems go for Doncaster.

"I think Johnny will ride him."

Ursa Major has made great strides since making his racecourse debut in March.

After winning one and finishing second twice in his first three starts, he won two handicaps in good style before winning the Group Three Irish St Leger Trial at the Curragh last month.

John Gosden has won the world's oldest Classic for the last two years and is contemplating fitting Michelangelo, one of his three likely runners this weekend, with blinkers for the first time.

The Newmarket trainer fitted Arctic Cosmos with the same headgear when he landed the Classic two years ago and is set to repeat the trick this weekend.

Gosden told British Champions Series TV: "I think Michelangelo would be a strong possibility (to wear blinkers) for the same reason (as Arctic Cosmos).

"He's a very genuine horse but he's quite dreamy and lacks focus. I've popped them on him, William was happy with them on, just to give him focus."

Michelangelo is set to be joined by pacemaker Dartford, as well as his Great Voltigeur Stakes-winning stablemate Thought Worthy.

Gosden is seeking to not only foil Camelot's quest for the Triple Crown, but also to complete a hat-trick in the race after Masked Marvel's triumph 12 months ago.