On her racecourse debut, Circus Ring contested a division on the Princess Maiden Stakes over six furlongs at Newmarket Racecourse in July. She was always among the leaders and accelerated clear of the field in the last quarter mile to win easily by seven lengths from Wintergrace. Later in the month, the filly was moved up in class for the Group ThreePrincess Margaret Stakes over six furlongs at Ascot Racecourse. She started the 4/6 favourite against a field which included several highly regarded fillies including Fairy Tern, Atossa and Silojoka. She produced what Timeform described as "one of the most breathtaking displays by a two-year-old filly that we have seen in a long time", taking the lead approaching the final furlong and sprinting clear of the field to win by ten lengths. At York Racecourse on 19 August, Circus Ring started the 1/4 favourite for the Group Two Lowther Stakes, in which her rivals were headed by the Cherry Hinton Stakes winner Travel On. Circus Ring traveled very easily throughout the race and Swinburn spent the closing stages looking round for non-existent dangers. Her winning margin of two lengths from Travel On was described by Timeform as being an inadequate measure of her superiority over her opponents. Circus Ring was being prepared for a run in the Group One Cheveley Park Stakes when she fell lame in mid-September and was retired for the season.
1982: three-year-old season
Circus Ring began the 1982 season as the clear favourite for the 1000 Guineas, despite doubts about her stamina and ability to recover from her injury of the previous season. Two weeks before the Newmarket classic she performed poorly in a training gallop and was withdrawn from the race. She eventually reappeared for the Coronation Stakes at Royal Ascot in June. She looked fit and well and ran well for much of the race but faded badly in the closing stages and finished last of the eight runners behind Chalon.
Assessment
In 1981, the independent Timeform organisation gave Circus Ring a rating of 122, making her the highest-rated two-year-old filly of the season. The experienced racing journalist Peter Willett compared Circus Ring's performances to those of Mumtaz Mahal and Myrobella. In the official International Classification she was rated the joint-best two-year-old filly in Europe, equal with the Fillies' Mile winner Height of Fashion and the French-trained Play It Safe.
Stud record
Circus Ring was retired from racing to become a broodmare at the Snailwell Stud before being exported to Australia in the mid 1990s by the Coolmore Stud. She produced no known foals after 1999 and died on 25 November 2009. Circus Ring's foals:
Douglas Fir
Circus Act, dam of Brave Act and Comic, the dam of Viva Pataca and Laughing