1944: two-year-old season As a two-year-old in 1944, Sun Stream was among the best of her generation. She won the Bedford Stakes over five
furlongs at Newmarket in spring and then moved up in class for the Queen Mary Stakes in June. The race, traditionally part of the
Royal Ascot meeting, was run at Newmarket from 1941 to 1944. Ridden by
Harry Wragg, she won the race at odds of
100/30. In autumn, Sun Stream ran in the six furlong
Cheveley Park Stakes, Britain's most prestigious race for two-year-old fillies. In a closely contested three-way finish she was beaten into third place by Sweet Cygnet and Neola.
1945: three-year-old season Sun Stream began her three-year-old season in the seven furlong Upwell Stakes, a now discontinued race which served as a trial for the 1000 Guineas, in which she finished second to Exotic. A month later, Sun Stream returned to the July course on 8 June for the Oaks Stakes. Although the race was not run at
Epsom Downs Racecourse it was given its traditional name: wartime runnings at Newmarket had been known as the "New Oaks". The relaxation of wartime restrictions on transport resulted in a huge crowd converging on Newmarket, leading to serious traffic congestion at the course. She started the 6/4 favourite in a field of sixteen fillies. In what was described as "one of the most exciting classic finishes ever contested", Sun Stream won the race by a short head and three quarters of a length from the
Aga Khan's Naishapur and Solar Princess. The veteran Harry Wragg was given a great deal of credit for the "mastery" he displayed in the race. She had a particularly hard race in the Oaks and did not compete again. ==Assessment and honours==