A tall, but quiet and unassuming right half, he was signed by Herbert Chapman's Arsenal in December 1926 for £200 and turned professional.
In the new "WM" formation that Chapman and Arsenal captain Charlie Buchan pioneered, Roberts served as the tall "stopper" centre half in the middle of defence; at the time this was a new tactic, created in response to the 1925 relaxation of the offside law, but soon became a ubiquitous position in English football.
He played in Arsenal's 2–1 victory over Sheffield Wednesday in the Charity Shield at Stamford Bridge in October 1930.
Roberts' long and successful career with Arsenal came to a sudden end early on in the 1937–38 season, when he broke his leg in a match against Middlesbrough and was subsequently forced to retire.
He died whilst on duty at the age of 39 from erysipelas, and was buried at Southgate Cemetery, north London;[3] he was one of the 9 Arsenal players to perish serving in the war.