Usworth, Sunderland born right back Billy Cook began his football career with North Eastern League Hebburn Argyle in 1910 and signed for First Division Sheffield United in May 1912, making his Football League debut that September at Bradford City. He soon became a regular in The Blades’ first team, forming a partnership at full back with former Hebburn left back Jack English, and missing only 7 games before the suspension of football due to the onset of the First World War in May 1915. He was part of The Blades’ 1914 FA Cup semi final team that narrowly lost to eventual winners Burnley after a replay at Goodison Park, and the following season he missed only one match in their 1914-15 campaign which saw them go one better, reaching the 1915 FA Cup Final, where he played as they beat Chelsea 3-0 at Old Trafford in the so called “Khaki Cup Final”.
He spent 15 years at Bramall Lane playing both sides of World War One, always in The First Division, and was again a losing FA Cup semi finalist in 1923 as The Blades went down to eventual winners Bolton Wanderers at Old Trafford. Cook then missed only one game in 1923-24 as Sheffield United finished 5th in the League Championship, before he was again an FA Cup winner with The Blades in the 1925 Final, when they beat Cardiff City 1-0 at Wembley Stadium. In 1925 it was said of him “A most consistent club back, it is singular that he has never been invited to play for his country or the League”. However he lost his place inSeptember 1926 and played his last game for the club in January 1927, having appeared 297 times for Sheffield United without ever scoring, before being transferred to non league Worksop Town in August 1927, already in his late 30’s, where he played until his eventual retirement.