Rutherglen, Lanarkshire born goalkeeper Willie Robb began his football career with Rutherglen Welfare in 1910 and played for Eastern Burnside in 1911 and Kirkintilloch Rob Roy in 1912 before joining Second Division Birmingham in 1913, for whom he made his Football League debut at Bury in February 1914. Initially understudy to Herbert Crossthwaite and Stan Hauser, playing only twice in his debut season, he made the gloves his own in 1914-15 when he was ever present for The Blues, however the advent of the First World War saw him return to Scottish football after 45 appearances for Birmingham.
He played for Vale of Leven in 1915, Royal Albert in 1916, Third Lanark from 1917 to 1920 where he made 43 appearances, playing for Scotland in an unofficial wartime international in 1918, and on loan for Armadale in 1919 before joining Glasgow Rangers in 1920. He stayed with Rangers for six years making 251 appearances for them and from the end of the 1919-20 season until midway into the 1925-26 season, Robb played in every Scottish League and Scottish Cup match that Rangers were involved in. This run came to an end on 31st October 1925, after an astonishing 241 consecutive matches.as he was selected for Scotland in a 3-0 win over Wales at Ninian Park, Cardiff that day, keeping a clean sheet on his debut. He played twice for The Scottish League while with Rangers, making his debut against The Irish League in a 3-0 win at Ibrox in January 1921, winning a further representative cap in October 1924, again in a 3-0 win over The Irish League, the match played at Tynecastle.
Robb lost his place in January 1926 and left Ibrox in the summer to move to Hibernian. He won a second Scotland cap while with Hibs, playing in a 2-1 win over Wales at Wrexham in October 1927, but he lost his place in the Hibernian team in 1930 after dislocating a finger, having made 137 appearances for them.
Returning to England, Robb joined Southern League Champions Aldershot in 1930 and was still at the club when they gained election to the Football League in 1932, indeed he was an ever present for their first two seasons as a League club and missed only two games in their third. He played 199 matches for them in their League status era, before playing two seasons for Guildford City from 1937, whom he helped win the Southern League Championship in 1937-38. He played for Regent Star in 1939 and retired later in 1939 with the outbreak of the Second World War at the age of 44.