On his only appearance as a two-year-old in 1987 Doyoun won the Westley Maiden Stakes over seven furlongs at Newmarket Racecourse in autumn.
On his three-year-old debut, Doyoun appeared at Newmarket in April for the Craven Stakes, a trial race for the 2000 Guineas in which he was matched against Warning, the previous season's top-rated two-year-old.