1913 and then for Avondale in 1914, but emerged into senior football with Glentoran in the immediate post First World War period, having joined them from Avondale in 1916. His big frame and rambunctious style of play belied his scientific play and delicate footwork. He played at inside left in all three matches it took to settle the 1919 Irish Cup Final in Linfield’s favour, his runner’s up medal being his only piece of silverware won.
Transferred to new Third Division (South) club Luton Town in May 1920, Mathieson made his Football League debut that August in the same team as the likes of Ernie Simms, Bookman, George Lennon and future Arsenal player Arthur Roe in Luton’s disastrous inaugural League fixture, a 9-1 thrashing at Swindon Town. Happily things rapidly improved and Mathieson bagged 10 goals that season as Luton finished in the top half.
Towards the end of the season he won his first cap for Ireland alongside Bookman against Wales at The Vetch Field, Swansea in a 2-1 defeat in April 1921. The Irish duo were to take to the field together again in Ireland’s match against England in Belfast in October 1921. Leading the line for the English was Luton team-mate Ernie Simms, the first time that one club had supplied three forwards for an international and all three from the Third Division.
In Mathieson’s second season Luton finished in fourth place in the League but he played less regularly in the second half of the campaign and after 16 goals in 56 appearances for The Hatters he moved to Third Division (South) Exeter City in July 1922 and made a scoring debut in a 1-0 home win over Brighton & Hove Albion, scoring 4 times in 29 games over a single season with The Grecians before moving to non league Workington in the spring of 1923.
He soon returned to Football League with New Brighton, signing in August 1923 and enjoying four seasons on The Wirral, scoring regularly and being the club’s top scorer in 1925-26. When Mathieson moved back to Ireland to join Coleraine in 1927, he had scored 38 goals in 140 New Brighton appearances. Already in his mid 30’s, he returned to Irish League football, first with Coleraine in 1927, and after a spell in Canada and The United States, latterly playing for Toronto Ulster United, he played for Holywood Rangers on his return in 1930 before returning to Glentoran in 1931 playing for The Glens until his retirement.
His brother John as also a professional footballer who played for Dundalk, Ards and New Brighton.