The Sea The Stars colt was last seen in action in August, winning the Group 3 Tattersalls Acomb Stakes in superb fashion on the Knavesmire.

Ballydoyle stablemates have impressed in a series of recent Derby trials, but The Lion In Winter remains at the head of the market for the most famous Classic of them all.

Now O’Brien has The Lion In Winter set to take his seasonal bow on the Knavesmire in this week’s £180,000 Group 2 – a renowned proving ground for potential Epsom horses, with eleven previous double winners.

O’Brien said: “We’re delighted that it looks like he’s going to make it. We weren’t sure he would – he’s been off a long time. But with the Derby in mind, it was the perfect prep. Obviously, it’s a very good Derby trial. 

“There’s two more two days to go, but it looks like he’s going to be fine. He’s going to improve a ton from whatever he does.

“Hopefully, he’s going to run well and that we’ve enough done with him to help him to run well. But I’m looking forward to it and to see what’s going to happen.

“It’s going to be very interesting. Hopefully, we have him in a good enough place to show what his potential could be.”

The Lion In Winter has not raced beyond seven furlongs before and Thursday’s extended 10-furlong race appears likely to indicate whether he will have the necessary stamina for the Derby 

O’Brien said: “You can never be sure. He doesn’t work like a mile and a half horse, really. He works like a miler. 

“I know most Sea The Stars do stay, but obviously we’re going to have to wait and see first before we can be really sure of anything.”

O’Brien is planning to send just one runner for the race, as is the case for Wednesday’s Group 3 Tattersalls Musidora Stakes, for which he has declared Whirl.

She landed a Group 3 as a two-year-old before finishing sixth of nine when taking on her elders over a mile at The Curragh in the Park Express Stakes in the first half of April.

O’Brien said: “We had to give her time to get over that and then decide where we want to go and the Musidora looked the perfect race if she was going to be an Oaks filly. We always thought she wanted much further than a mile – always thought that she would stay.”

O’Brien also confirmed that Continuous is another intended Ballydoyle runner at York. He ran down the field in the Dubai Gold Cup at Meydan in April and comes back in trip for the Group 2 Boodles Yorkshire Cup on Friday.

The Dante Festival is York’s first meeting of 2025 and gets underway on Wednesday, with the first race set to take place at 2.10pm.