Anthony "Tony" William Greig (born October 6, 1946) is a former English test cricketer and currently a commentator.

Born in South Africa, Greig qualified to play for England by virtue of his Scottish father. He was a tall (6' 7") all-rounder who bowled both medium pace and off spin. He became captain of the national side from 1975 to 1977, and was also captain of the Sussex county side. Greig's younger brother Ian, also played test cricket.

He was a sometimes controversial figure. His most daring act was when he helped Kerry Packer start World Series Cricket by signing up many of his English colleagues as well as West Indian and Pakistani cricketers, a move which cost him the captaincy of England. He is also noted for a controversial run-out of Alvin Kallicharran in a test match against the West Indies in 1974. In a later match, he turned in a personal performance that saved the series for England. He also clashed with Australian fast bowler Dennis Lillee on the 1974/75 Ashes tour in Australia.

Greig was born at Queenstown in the Eastern Cape in Border Province, South Africa to a Scottish immigrant father and a South African-born mother. Educated at Queen's College, Queenstown,South Africa, the choice of this school decided his cricket destiny. Many ex-Sussex players had been recruited to coach the cricket team at Queen's College: during Greig's schooldays, Jack Oakes, Alan Oakman, Ian Thomson, Ron Bell, Richard Langridge and Mike Buss all came out for a winter of work in the sunshine. All of them noticed Greig's developing abilities, which led to a trial at Sussex when he was 19. He had already made a first class debut for Border Province in the Currie Cup. Greig's father helped him decide between university study or pursuit of the Sussex offer. "He used to slam into me for not reading enough, for being generally immature. He would look at me sometimes and say 'Boy, when I was your age I was fighting a war', but in the end he grinned and said: 'Go over to England for one year, one year mind and see what you can do'" Wisden 1975 .

When he scored a swashbuckling 156 in 230 minutes against a strong Lancashire attack in his first game for Sussex, his future direction changed irrevocably. He wrote a brief note to his father, to tell him he wouldn't be coming back to go to university. Greig set a goal of making the England test team in six years, which was interesting as his home nation had yet to be banned from international cricket. Indeed, Greig returned to play in South Africa during the winter for a number of years, eventually transferring to Eastern Province for the 1970-71 season.