Strathclyde, Glasgow born centre forward Billy Gillespie began his football career with hometown junior club Strathclyde and did enough to be signed by Second Division Lincoln City along with elder brother Matt in the summer of 1895, making his debut in an FA Cup tie at Peterborough Association that October, a match which is to this day Lincoln’s record victory, Gillespie scoring twice and his brother scoring a hat-trick in a 13-0 victory, his Football League debut coming a week later in a defeat at Notts County. Gillespie managed 11 League goals in his debut season, finishing as The Imps’ top League goalscorer, and he scored 4 goals in another FA Cup tie, an 8-0 win over Worksop Town in December 1896, before being signed by Second Division Manchester City in January 1897.
He scored on his debut for The Citizens in a defeat at Darwen and was an ever present in 1897-98 as his 19 goals in the campaign helped City finish third in the Second Division. He was again an ever present in 1898-99 as they won the Second Division Championship, with Gillespie scoring 18 goals in the campaign, including a hat-trick in a 7-2 win over Grimsby Town on the opening day of the season. After two seasons of consolidation in the top flight, Manchester City were relegated in 1901-02 despite Gillespie scoring 15 goals, including all four in a 4-1 win at Blackburn Rovers in April 1902, but his most prolific season followed in 1902-03 when he fired City straight back to the top flight in 1902-03 as Second Division Champions, Gillespie scoring 30 goals in 33 games, including hat-tricks against Glossop and Woolwich Arsenal.
He was Manchester City’s leading goalscorer for the third successive season in 1903-04 with 21 goals, including three in their run to the 1904 FA Cup Final, including a semi final goal in their 3-0 victory over Sheffield Wednesday at Goodison Park. He then played as Billy Meredith’s goal was enough to beat Bolton Wanderers 1-0 at The Crystal Palace, giving Manchester City their first major honour.
In 1904-05 Gillespie was the team’s fourth highest scorer with 7 League goals in 16 games behind Sandy Turnbull who scored 19 goals and Billy Meredith and Frank Booth who both scored 8 goals. Manchester City finished third in the League that season, two points behind champions Newcastle United. At the end of the season The Football Association conducted an investigation into the financial activities of Manchester City and discovered that the team had been paying their players extra monies above the maximum wage. The Football Association ruled that manager Tom Maley should be suspended from football for life while seventeen players were fined and suspended until January 1907. Gillespie refused to pay his fine and instead emigrated to the United States, where he played for General Electric. In nine season he made 231 appearances for Manchester City and scored 132 goals.
He was the younger brother of Matt Gillespie, who played for Blackburn Rovers, Accrington, Strathclyde, Leith Athletic, Lincoln City and Newton Heath (later Manchester United).