Derby headache in store for Moore as O'Brien talks up chances of Mogul

Aidan O'Brien says Ryan Moore's decision on who to ride in Saturday's Investec Derby will "not be an easy one" after he again talked up the prospects of 7-1 shot Mogul, who he says came out of Ascot "bouncing and with a big smile on his face".

O'Brien could run as many as six in the Derby as he seeks to become the most successful trainer in the race's history with an eighth win and, of his seven possibles for the race, the only one likely to miss Epsom is Armory. The Irish 2,000 Guineas fourth, a 25-1 chance, is set to head to Chantilly for the Prix du Jockey Club on Sunday instead.

It will be left until the last possible minute before deciding what Moore will ride in his search for a third Derby, but the master trainer spoke in glowing terms of Mogul and said the only way he could win the Derby this year was by running him in the toughest trial – the King Edward VII Stakes – in which he finished fourth.

O'Brien said on Tuesday: "I would say we will run five anyway, possibly six at Epsom. I'm not sure who Ryan [Moore] will ride yet. It's not going to be an easy one for him, that's for sure. He obviously hasn't been able to sit on them here so that will make it a bit harder for him.

Aidan O'Brien is not sure who Ryan Moore will ride in the DerbyCredit: Edward Whitaker

"He will wait and see what draws each of them get and then we will discuss each of them individually after declaration time before he decides. It definitely won't be easy this year.

Aidan O'Brien's seven Derby contenders (with current ante-post price)

Russian Emperor (7-1)
Mogul (7-1)
Vatican City (8-1)
Armory (25-1)
Serpentine (25-1)
Mythical (40-1)
Amhran Na Bhfiann (50-1)

The trainer added: "We had to do an unorthodox thing with Mogul – we wanted one race to do the job of two at Ascot. To give him a chance of winning a Derby, we had to run him in the toughest trial. The risk was that he was going to get beaten but we felt it was a risk worth taking. What we've seen since has really impressed us – he's bounced out of Ascot with a big smile on his face begging for more."

"Russian Emperor will run. He's tough, hardy and relaxed. He's come out of the race at Ascot lovely and he's definitely in the mix with regard to what Ryan might ride. He was a fit horse at Ascot as he had two runs before it.

"We obviously don't know whether Vatican City will stay the trip or not, but we're hopeful he will. That was a very good run from him in the Irish Guineas and he's come forward nicely from it. He only just made it to the Guineas, he was only just about ready to run. I would imagine it will be one of those three who Ryan will ride."

Moore won the Hampton Court Stakes on Russian Emperor (right) at Royal AscotCredit: Edward Whitaker

Of his other contenders, O'Brien said: "It looks like Armory will head to France. Mythical has improved a lot since the Curragh and we think you'll see a different horse at Epsom. We're leaning towards Epsom with him, as we are with Serpentine, who came out of his maiden win the other day in good shape.

"Wayne [Lordan] said he couldn't stop him after the line that day. Amhran Na Bhfiann has come forward nicely since his maiden at Leopardstown. That maiden has turned out incredibly well. He's a lovely, big, open galloper who will get a mile and a half well."

With the Irish Oaks taking place at the Curragh on July 18, O'Brien is not willing to send his retained riders across to Epsom unless the 14-day quarantine rule is relaxed in the meantime.

The champion trainer said: "It looks like the quarantine situation might be changing in England, but I'm not sure what's happening in Ireland and whether it will be lifted here before Saturday. There is talk maybe of something happening next Thursday but I’m not sure. I've been in contact with Jennifer Pugh [IHRB chief medical officer] to see what might happen, but it's all up in the air at the moment.

"We will have to decide about jockeys on Thursday but we don't know yet what the situation will be with our own lads. We don't want them missing the Irish Oaks. There are plenty of very good riders in England that we can use if we need to.

"We have James [Doyle], William [Buick] and Adam [Kirby] and maybe some of our own people will head over. If our lads go there, the way the restrictions are, they can't ride for two weeks here.

"You don't want to mess anybody around. We'll try to have people on hold and available, but we don't want to mess anybody around or offend anybody. It's difficult, but everyone is very understanding. The lads will put it all together and hopefully they will come up with the right solution."

Investec Derby entries & betting

Read more on the Investec Derby:

'It's all systems go' – Dettori delighted after riding English King in key work

A year to remember continues for jockey Ben Curtis after Derby call-up

Stuart Riley assesses the Derby and Oaks as entries for both races are revealed

Owners back on course for Derby day with test fixtures set for Wednesday

Which jockeys will O'Brien turn to for his Classic squad at Epsom?

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