Blacklock (1814 – 24 February 1831) was a British Thoroughbred racehorse who won seventeen of his twenty-three races.

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.

Whitelock was a son of St. Leger and dual Doncaster Cup winner Hambletonian, who was only defeated once in his career.

[2] Blacklock, who was then unnamed and raced under the name "Mr. Kirby's b. c. by Whitelock, dam by Coriander", made his racecourse debut on 23 August 1816 at York in a sweepstakes of 20 guineas each for two-year-olds.

[6] Racing in Watt's colours (Harlequin)[7] and ridden by jockey J. Jackson, Blacklock made his final start as a two-year-old at Doncaster on the 24 September when he competed in another sweepstakes of 20 guineas each.

[6] Blacklock, still unnamed, had his first race as a three-year-old in the St. Leger Stakes at Doncaster on Monday 22 September.

[9] Blacklock appeared like he was going to win easily and Jackson eased him up in the final furlong (200 metres) of the race.

[9] Two days after the St. Leger, Blacklock faced St. Helena over the same course and distance in the Gascoigne Stakes,[12] which he won easily.

[13] Twenty-four hours later, Blacklock lost to The Duchess in the Doncaster Club Stakes over two miles.

[14] On 8 October at Richmond he won a sweepstakes of 20 guineas each, beating four rivals, with Boroughman finishing second.

[15] Later in the day Blacklock won the Dundas Stakes, beating Rasping, D.I.O and Shepard into second, third and fourth respectively.

[18] Blacklock did not race again until August at York, where he ran in the four-mile Great Subscription Purse for four-year-olds.

[24] At Richmond in October he won his second Dundas Stakes, this time beating King Corney.

Later in the day Blacklock finished last of four runners behind winner Doctor Syntax in the Richmond Cup over four miles.

[26] By the time The Richmond Cup was run Blacklock was apparently unwell and was coughing repeatedly during the race.

[29] At the York August Meeting, Blacklock faced three rivals in the four-mile Great Subscription Purse for five-year-olds and older.

[30] Blacklock's final race came two days later, when he finished second to St. Helena in a sweepstakes of 25 guineas each over two miles.

[36] His progeny included: Blacklock died on 24 February 1831 at Bishop Burton after rupturing a blood vessel when covering a mare.