Alan Sugar was previously the chairman of Tottenham Hotspur Football Club before becoming the central investor on the British version of Dragon's Den's related format, The Apprentice. Sugar served as Tottenham's chairman from 1991 to 2001.
His business career began with Amstrad, the consumer-electronics company he founded in 1968. Although Sugar is widely associated with The Apprentice rather than Dragon's Den, he is frequently confused with the dragons because both programmes feature wealthy businesspeople judging entrepreneurs.
This distinction matters: Sugar was not a regular Dragon's Den investor. The question identifies his football-chairman history and separates him from the actual Dragon's Den panel, whose members included Peter Jones, Deborah Meaden and Theo Paphitis.