Mossley, Lancashire born right half Bill Bottomley began his football career with Greenfield Athletic in 1903 and played for Edgehill in 1904, Mossley Britannia in 1905 and Fallsworth in 1906 before signing for Second Division Oldham Athletic in October 1907, making his Football League debut against Barnsley the same month. After 13 appearances for The Latics he was signed by First Division Manchester City in May 1908 but only appeared once for them, in a win over Notts County that October, in what proved a relegation season.
In 1909-10 he made 18 appearances during their campaign which ended with City winning the Second Division Championship to immediately reclaim their top flight status, and Bottomley made 19 appearances in each of the following two seasons as The Citizens consolidated their position in the First Division, scoring his first career goal in a 1-1 draw at West Bromwich Albion in March 1912. This was followed by a second goal in a 2-2 draw with Tottenham Hotspur on Christmas Day 1912 in what would prove his best season for the club, with 34 appearances as Manchester City finished sixth in the League Championship. However he lost his place in November 1913 and played only once in 1914-15, which proved the final season of peacetime football before the onset of the First World War forced its suspension.
Bottomley enlisted in December 1915 and served as a private in the Army Service Corps during the First World War and continued to guest for Manchester City in wartime league football, but retired before peacetime football recommenced.