Aidan O'Brien confirms Arizona on course to take on Siskin in Phoenix Stakes

Aidan O'Brien is set to send out his big guns to take on Siskin in Friday's Group 1 Phoenix Stakes at the Curragh as Ireland's champion trainer bids to bring Ger Lyons' colt's unbeaten record to an end in a race he's won with the likes of George Washington, Holy Roman Emperor and Mastercraftsman.

O'Brien could run as many as four, including Coventry Stakes victor Arizona – priced up at 2-1 with Paddy Power – while he also plans to include July Stakes winner Royal Lytham and Monarch Of Egypt, who was second to Siskin in June's Group 2 Railway Stakes over the same course and distance.

A decision on the participation of recent Naas winner Harpocrates will be made closer to the time, with O'Brien keen to stress running plans could change.

He said: "At the moment we're thinking of running Arizona, Royal Lytham and Monarch Of Egypt, and we'll make a decision on whether or not we run Harpocrates – who won at Naas the other day – closer to the time."

O'Brien, who has won the Phoenix Stakes 16 times, added: "That's the way we're thinking at the minute, but nothing's set in stone and things could change, with the forecast and how horses are before the race."

Siskin sees off Monarch Of Egypt in the Railway Stakes: the pair are set to renew rivalry on FridayCredit: Patrick McCann

Arizona could provide Siskin, bidding to land a first domestic Group 1 for Ger Lyons and Colin Keane, with his sternest test to date. O'Brien has been happy with the colt since Royal Ascot, and providing an upbeat bulletin on his chances said: "We're happy with where they all are. Arizona has been good since winning the Coventry Stakes at Royal Ascot. He's a very straightforward horse and everything has gone well with him since."

Monarch Of Egypt may have already finished behind Siskin, a 7-4 favourite for Friday's race, but O'Brien is expecting an improved display from his charge, who was returning from a break in the Railway.

Speaking about Monarch Of Egypt and the rest of the Ballydoyle challenge, O'Brien said: "I think Monarch Of Egypt will come on a lot for his run in the Railway Stakes.

"He was only ready to start back in that race, which was something we said at the time, and he's been very well since. Royal Lytham also came out of Newmarket well."

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