Battle lines drawn by O'Brien

Jockey Joseph O’Brien is hoping his loyalty to Battle Of Marengo can yield an Investec Derby double at Epsom today.

O’Brien had the choice of five horses trained by his father, Aidan, although only three have a realistic chance of glory.

Battle Of Marengo has been beaten once in six starts, but never when ridden by O’Brien, who believes he has a good chance of following up last year’s triumph with Camelot after winning two recognised trials in Ireland.