Glentoran had recorded their highest points tally under owner Ali Pour last season, while striker Pat Hoban enjoyed a prolific debut campaign.
During Devine's tenure, the club have lifted the County Antrim Shield, but have struggled to push for the league title since the 2008-2009 season.
There was plenty of optimism around the Oval during the summer, accompanied by excitement regarding several new arrivals.
Defender Zeno Ibsen Rossi impressed on the European stage, while the late re-signing of Northern Ireland international Conor McMenamin looked to provide a timely creative boost.
Yet, six games into the season, the mood has changed and players have left the pitch to choruses of boos from large sections of their support after some dire performances.
The investment has not led to a single top-two finish in the Irish Premiership, while the side has also struggled in European games and failed to reap financial rewards.
For Devine and his players, the next few weeks will be crucial as fixtures continue to come thick and fast.
Coleraine's visit to the Oval on Tuesday will provide a real acid test and the outcome may go a long way in deciding the manager's future.