Thomas joined first class team Newport in 1885 and while at the club was utilised in multiple positions throughout his career.
Thomas played as fly-half, scrum-half, centre, half back and wing and had a very high score rate, with 99 tries in 215 appearances for Newport.
During Newport's 1891/92 invincible season, he partnered legendary Welsh captain Arthur Gould at centre.
In 1888, Thomas was selected to represent Wales for the first time in a game against Ireland as part of the 1888 Home Nations Championship.
Wales won the match by one goal and two tries to nil, but Thomas was on the losing team when his club side, Newport, faced the Māoris four days later.