10/25/2001 12:00AM

O'Brien solid in Racing Post


Aidan O'Brien will have three of the six starters in the $250,000 Racing Post Trophy for 2-year-old colts and fillies at Doncaster Racecourse in Yorkshire, on Saturday. It is the final Group 1 race of the British season.

The most accomplished of O'Brien's three, Castle Gandolfo, should prevail. A seven-length winner of the Group 3 Beresford Stakes at the Racing Post distance of a mile at the Curragh on Oct. 14, he can continue O'Brien's domination of the European juvenile division this year.

* Captain Rio, a three-time veteran of the sales ring, followed up on his victory in the $267,000 Redcar Two-Year-Old Trophy with an eight-length hammering of War Zone in the Group 2 Criterium de Maisons-Laffitte Thursday. Trained in England by Roger Whitaker, the Captain Rio led throughout, getting the six furlongs in 1:14.30 on heavy ground.