Career
McStay began his senior career when he joined Celtic from Larkhall Thistle in 1912, although he was immediately loaned to Ayr United, spending the following four seasons with the Somerset Park club He had further spells away from Celtic Park during the latter years of the First World War, assisting Irish sides Distillery and Belfast Celtic, before establishing himself in the Celtic first team McStay earned his first selection for the Scottish national side in 1921.
He made his debut in a 2-1 defeat of Wales at Pittodrie and also played in the match against Ireland two weeks later.
McStay also appeared 10 times for the Scottish League XI. Having helped Celtic to the 1917, 1919 and 1922 League titles, In 1923, McStay played one game with New York Field Club in the American Soccer League. He was appointed captain of Celtic upon his return to the club later that year, taking over from William Cringan, and held the role for six years.
He retired from playing in 1930 and was later manager of Glentoran for a period in the mid-1930s. McStay has several family footballing connections.
