article_snippet: Man River among seven of Aidan O’Brien's horses in the first nine in the ante-post betting for Derby .
article_snippet: Man River among seven of Aidan O’Brien horses in the first nine in the ante-post betting and Ladbrokes make it even money that an O’Brien horse wins the Derby.
highlights_snippet: Aidan O'Brien has seven horses in first nine of ante-post betting for Derby .
  