Blacklock was a British Thoroughbred racehorse who won seventeen of his twenty-three races. As a two-year-old in 1816 he was undefeated in three starts. In his first race as a three-year-old he finished second in the St. Leger, a neck behind Ebor. He then won four races in two weeks, including the Gascoigne Stakes and Dundas Stakes. In 1818 he recorded several wins including two of the Great Subscription Purses at York. He won a third Great Subscription Purse in 1819, along with the York Gold Cup. After retiring from racing, Blacklock became a successful stallion and was champion sire of Great Britain in 1829, the year his son Voltaire won the Doncaster Cup. He was owned by Thomas Kirby as a two-year-old, before being purchased by Richard Watt, who owned him for the remainder of his racing career. Blacklock was trained by Tommy Sykes.

Ebor (1814–1822) was a British Thoroughbred racehorse and sire best known for winning the classic St Leger Stakes in 1817. Bred, trained and raced in Yorkshire, Ebor was lightly campaigned, running only six times in a three-year racing career which was confined to the meetings at York and Doncaster. He won four times, one of these being a walkover. His St Leger win saw him upset the favourite Blacklock in a dramatic and controversial finish. After his retirement he became a breeding stallion but died before he could make an impact at stud.