Cronberry, Ayrshire born right half George Halley started his football career with Glenbuck Cherrypickers in 1906 and joined Scottish League Kilmarnock in 1908, making his Scottish League debut at Celtic in August 1908. In three seasons at Rugby Park, when he scored 6 goals in 84 appearances for Killie, he impressed enough to be selected for The Scottish League, playing in a 3-2 victory over The Football League at Ewood Park in February 1910, before moving to Second Division club Bradford Park Avenue in May 1911, making his Football League debut that September at Birmingham City.
Halley played 70 games for Park Avenue scoring 8 times before moving to Burnley in March 1913, helping them to promotion at the end of the season as Second Division runners up. At Burnley he was a member of the team that won the FA Cup in 1914 when they beat Liverpool at The Crystal Palace, before his career was interrupted by the First World War, during which he served in the British Army as a sapper in The Royal Engineers and saw action in France and Mesopotamia, before being posted to India in 1919.
After his return to Turf Moor he re-established himself in the first team from October 1919 as Burnley finished runners up in the League Championship, and the following season Halley played 26 League matches as they won the League Championship in 1921, playing 34 games the next season as they finished third in their defence of the trophy. After 153 games for The Clarets, scoring 5 goals, he moved to Southend United in November 1922 where he made 23 more appearances for The Shrimpers before joining non league Bacup Borough in 1924 ahead of his eventual retirement.