The son of Sadler’s Wells doesn’t have an easy task off top weight in this Group Three, but may prove up to the task.
The English Leger winner showed ten furlongs holds no real fears for him when beating Napper Tandy by three parts of a length in a Listed event at Leopardstown in March.
He faces two particularly smart opponents now in Nysaean and the unbeaten in three races, Tolpuddle.
But both of those horses would prefer plenty of cut in the ground and Brian Boru can prove too strong for them.
O’Brien’s Russian Blue is fancied to become the first juvenile to score twice this season, in the Choisir EBF Race.
As a son of Danehill, he could have been expected to struggle on the heavy surface first time up at headquarters, but made light of it to win by three lengths.
He can give 7lbs and a beating to Globalized, who performed with distinct promise when a length and a half runner-up to another Ballydoyle inmate, In Excelsis, at Tipperary.
O’Brien has a more than useful hand with Grand Reward and Newton in the Rock Of Gibraltar Tetrarch Stakes.
Grand Reward never really produced on the raceccourse last season what he shows at home, but kept decent company nevertheless.
Preference, however, is for Newton who showed his current well-being with a game half a length defeat of Dabiroun at the Curragh last month.
Ability to handle fast ground will be vital at Limerick today and, on that basis, Rory Sunset is napped to land the opening maiden hurdle.
He was certainly disappointing when failing to justify odds of 1-2 at Down Royal last time, but has some smart form in bumpers when hearing his hooves rattle!
Michael Hourigan’s versatile King Carew gets the vote in the May Bank Holiday Handicap Chase.
He comes here in good shape, having run well when third to the dead-heaters, Kellys Craft and Boleyknowsbest, over flights at Punchestown last week.