[3] She was sent into training with Brian Swift at Loretta Lodge, Epsom She was sired by So Blessed, a sprinter who won the July Cup and the Nunthorpe Stakes as a three-year-old in 1968.
Her temperamental problems returned at Epsom later that month when she was withdrawn at the start after bolting, colliding with the running rails and injuring her jockey Lester Piggott.
[3] In June at Royal Ascot she was moved up in class for the Windsor Castle Stakes and finished fourth to the Irish colt Cooliney Prince after leading until inside the final furlong.
She was strongly pressed in the closing stages by the favourite Band Practice (a colt from the Dermot Weld stable) but stayed on well to win by a head.
In their annual Racehorses of 1980 Timeform described her as "an exceptionally speedy filly" with "tremendous nevous energy" but opined that her owners had wasted their money by entering her in the 1000 Guineas as she had no chance of staying beyond five furlongs.
[3] Swan Princess began her second season in a minor race over six furlongs at Folkestone in April and won by one and a half lengths from Silex.