Managing the club between February 1929 and September 1935, and guiding over the 1931 FA Cup run and second-place finish in 1933, Billy McDevitt had earlier played for Exeter City during the second half of the 1920s. Starting his career in Belfast football, and subsequently moving to Swansea Town, he joined the Grecians from Liverpool in 1925. He later managed in the Irish League with Bangor, Belfast Celtic and Distillery.  

Starting his career in Belfast junior football, he joined Swansea Town in 1921 where he switched from inside-right to centre-half before moving back to Belfast. Given a second chance in the professional ranks by Liverpool in 1922, a £300 fee was payable to Swansea who had retained his Football League registration. 

After playing just four league games for his new club, Billy switched to Exeter City and made his debut in a 3-0 home win over Queens Park Rangers on 23 September 1925. Having made 24 league appearances in his first season, he followed this up with 28, 36 and 21 over the next three seasons before his appointment as player-manager in February 1929.

Continuing to occasionally appear until the end of the 1929/30 campaign, Billy began to concentrate on management and successfully assembled the team which reached the quarter-finals of the FA Cup in 1931 and finished as runners-up in Division Three (South) in 1932/33. This often earned him the accolade of being the club’s ‘best-ever manager’ for many years to come.

Turning down an offer from Queens Park Rangers in 1933, Billy remained in charge at Exeter until September 1935 when he resigned. Scouting initially for Wolverhampton Wanderers in Ireland, he later took charge of Bangor, Belfast Celtic and Distillery ahead of his death in 1966.