The regional agency, part of newly merged Arena BLM, is understood to have pitched against the incumbent Mediaedge:cia, as well as other, undisclosed agencies.
CIA Medianetwork, one of Mediaedge:cia's predecessors, landed Rank Group's account in June 1997 and has had a relationship with it ever since.
Rank Group, which also owns betting outfit Blue Square and Mecca Bingo, has been reviewing its media, as first revealed by Media Week last week.
The company is reviewing its media requirements in the wake of tougher trading conditions, prompted by the smoking ban and a government crackdown on gambling machines.
In its latest results, pre-tax profits were up to £46.2m from £40.2m, despite a "significant deterioration" in trading conditions.
Rank hopes that a targeted media campaign will raise awareness of its brands, and has set aside an estimated £5m for media in 2008.