In the following year, he was transferred to the United States, where he recorded his most famous victory as he ended the undefeated streak of the Triple Crown winner Seattle Slew with a win in the Swaps Stakes.

J. O. Tobin was an "impressive-looking" brown colt, with a small white star bred in Maryland by his owner, George A. Pope Jr.

Tobin began his racing career with a win over Chain of Reasoning in the Fulbourn Maiden Stakes over six furlongs at Newmarket Racecourse on 8 July.

The form of the race was subsequently boosted when Durtal won the Cheveley Park Stakes and was rated the best two-year-old filly of the year in Britain.

Tobin was matched against the outstanding French two-year-old Blushing Groom in a highly anticipated race for the Grand Critérium over 1600 metres at Longchamp Racecourse on 10 October.

[5] When Murless retired at the end of the 1976 season, Pope brought the horse back to the United States, where he was trained by former jockey and U.S.

For his new trainer, the colt won the Coronado Handicap at Hollywood Park Racetrack in April and then finished fifth behind Seattle Slew in the Preakness Stakes.

There was no International Classification of European two-year-olds in 1976: the official handicappers of Britain, Ireland, and France compiled separate rankings for horses which competed in those countries.

He was the leading freshman sire at the Keeneland yearling sales in 1981 ahead of his old adversary, Seattle Slew but overall he was not a success as a breeding stallion.