At the age of three Donovan won The Derby and the St Leger: he failed to win the English Triple Crown owing to a narrow and probably unlucky defeat in the 2000 Guineas.

[4] Donovan appeared in the first week of the flat season to win the Brocklesby Stakes at Lincoln Racecourse "a bit cleverly"[5] by two lengths from the filly Poem.

He then took the Portland Stakes at Leicester, winning by three lengths from a field of twenty-four opponents for a prize of £6,000,[6] making the race more valuable than the Derby.

[7] In the £5,000 Whitsuntide Plate at Manchester Racecourse, Donovan was set to carry 136 pounds and suffered his first defeat when four lengths second to the well-fancied Chitabob.

Carrying top weight of 129 pounds he started 11/8 favourite in a field of fourteen and won in a race record time of 1:15.2,[12] beating Gulliver by two lengths.

[23] In the Newmarket Stakes over ten furlongs on 22 May Donovan "very easily"[24] defeated his stable companion The Turcophone, with Laureate third and Enthusiast fourth, leading to his price for the Derby shortening to 4/5.

[25] At Epsom on 5 June, Donovan (who arrived at the course with a security entourage of detectives and police constables)[26] started 8/11 against twelve opponents, including The Turcophone who was running as a pacemaker.

[27] As in his previous races in 1889, Donovan was taken directly to the start to be saddled instead of appearing in the paddock and parading with the other runners: the Duke explained that this was because of the colt's nervous or "fidgetty"[28] temperament.

After a short delay caused by false starts, the race got under way with The Turcophone setting a strong pace, while Tommy Loates settled Donovan in fourth place.

[31] Donovan was then sent to Royal Ascot for the Prince of Wales's Stakes over thirteen furlongs in which he started at odds of 2/9 despite carrying top weight of 131 pounds.

He started 8/13 in a field of thirteen with his main rival expected to be the Yorkshire-trained Chitabob[33] the colt who had defeated Donovan in June 1888, and who had recently returned after training problems.

Chitabob attempted to make all the running, but Barrett was always prominent on Donovan before taking the lead inside the final furlong and winning by two lengths.

[39] Donovan was considered by some to be a fortunate horse who had emerged in a generation with few other top class performers,[40] but by the end of the three-year-old season he was acknowledged by others as "a really great racehorse.