[1] Mathias served during World War I with the Royal Flying Corps, entering service in 1916 with the temporary rank of 2nd Lieutenant.
Mathias made his first-class debut for Glamorgan against Nottinghamshire at Cardiff Arms Park in the 1922 County Championship.
[7] He also made a single first-class appearance for Wales against Ireland in 1926 at Ormeau Cricket Ground, Belfast.
Wales responded in their first-innings by making 455/8 declared, with Mathias scoring 65 runs before he was dismissed by Gustavus Kelly.
Ireland were then dismissed in their second-innings for 266, with Mathias taking the wickets of Albert Anderson and Robert Bowers, to finish with figures of 2/23 from 7.1 overs.