Aidan O’Brien has underlined the scale of the task his son Joseph has in attempting to ride the 2,000 Guineas favourite Gleneagles at Newmarket in just over a month.

“The reality is that Joseph found making 9st last year very difficult and he’s heavier this year. The Guineas is only a month away and that’s 9st so whether he will be able to get back down to that I don’t know.

“Hopefully he will be back, but it will be tough. It’s something we will have to play by ear but Joseph won’t be put under any pressure in any way,” the champion trainer said.

O’Brien unveiled the cream of his Ballydoyle stables as 65 took part in post-race workouts at the Curragh, including Gleneagles and the Derby favourite John F Kennedy.

Most powerful

However the focus was mostly on jockeys and how riding arrangements at the world’s most powerful yard may unfold this year.

Joseph O’Brien came to the gallops sessions after finishing fifth in his first ever jumps race at Limerick earlier in the day, and amid continuing speculation regarding the 21-year -old’s chances of maintaining his career on the flat.

He insisted he will be riding at Dundalk on Wednesday but will continue to mix the flat with jumping although he was unable to make 9.5st for two of his father’s runners at the Curragh.

Ryan Moore was successful on one of them, The Warrior, and afterwards rode in all three Ballydoyle gallops, including on John F Kennedy.

There have reports of a likely increased link between Ballydoyle and one of the world’s leading jockeys in 2015 and Aidan O’Brien said: “Ryan is there and we have had a good working relationship with him over the last few years.”

O’Brien Jnr partnered Gleneagles in a one mile gallop, with Moore riding Highland Reel. Both are likely runners in the 2,000 Guineas.