Aidan O'Brien facing stern British challenge in pursuit of 13th Irish 2000 Guineas triumph

Trainer Aidan O'Brien speaks to jockey Ryan Moore after winning the Coolmore Stud Calyx Race with Treasure Isle at Naas last Sunday

Michael Verney

Aidan O'Brien may have a dozen wins in Saturday's Irish 2000 Guineas already under his belt but the Ballydoyle maestro faces a tough test to make it 13 with a pair of leading British raiders throwing down the gauntlet.

Richard Hannon Jnr sends Rosallion and Haatem to the Curragh as he bids to follow in the footsteps of his father, and namesake, after his trio of Irish Guineas successes (Don't Forget Me in 1987, Tirol in 1990 and Canford Cliffs in 2010).

Hannon reports red-hot favourite Rosallion (the mount of Sean Levey), second on his last start in the English 2000 Guineas, and Newmarket third Haatem (Jamie Spencer) to be in rude health.

“They did a piece of work on Sunday morning and Rosallion travelled like a genius,” Hannon said of the 11/10 market leader. “Haatem did what he normally does. He's very relaxed and just shows his well being.”

They will have to outgun a sextet from O'Brien, though, after the field for the €500,000 showpiece was cut to 11 with River Tiber and Unquestionable set to lead his team.

River Tiber was last seen when third in the Group One Middle Park Stakes in Newmarket at the end of September but the son of Wootton Bassett is ready for lift-off in the Irish Classic.

“Everything has went well with him. Obviously we were trying to split them all up and start off in different races. He was in Navan the other day and everything is good," O'Brien said.

“We think a mile is within his compass, although not guaranteed. We just thought we would start in the Guineas and if he didn't get it, he would go back to the Commonwealth (Cup, at Royal Ascot over six furlongs) or something like that. He is not short of speed.”

Unquestionable may not be as cherry ripe as his stablemate having suffered “a little blip a couple of weeks ago” and the Breeders' Cup Juvenile Turf hero may be seen to better effect at Royal Ascot, according to his trainer.

“He might not be as forward at River Tiber but the plan is to start him at the Curragh with a view to going to Ascot after that,” he said.

“He had a little blip a couple of weeks ago but he is back in full swing again but he did have it so because of that, he might improve a little more from the Curragh than River Tiber.”

Henry Longfellow is also entered but unlikely to run after recently disappointing when going off favourite in the French Guineas while impressive Leopardstown maiden winner Igor Stravinsky. Mountain Bear and The Liffey could also feature for him.

Tetrarch Stakes winner Bright Stripes is a rare Classic runner for Andrew Oliver while Atlantic Coast and Take Me To Church could also take their chance at big prices for Joseph O'Brien and Jack Davison respectively.