During her racing career, she was trained by Arthur Boyd-Rochfort's younger step-brother Henry Cecil at the Marriott Stables in Newmarket, Suffolk.
She took the lead in the closing stages and won by a neck from the Dick Hern-trained Regatta, with a long gap back to the other runners.
[4] Cloonagh made little impact on her three-year-old debut when she finished sixth behind Caspian in the Nell Gwyn Stakes over seven furlongs on good to firm ground at Newmarket Racecourse in April.
The Bedford Guineas Trial winner Annerbelle started favourite ahead of Daria (Athasi Stakes) with Cloonagh, ridden by Greville Starkey the 7/1 third choice in a twelve-runner field.
[2] In the Coronation Stakes at Royal Ascot in June, Cloonagh became very agitated before the start and ran poorly, finishing eighth of the nine runners behind Jacinth.
Cloonagh's juvenile form was not good enough for her to be assigned a weight in the Free Handicap, a ranking of the best two-year-olds to race in Britain.