Peter Brook has left Admiral Taverns after two years overseeing the pubco's 'Phoenix' division of around 700 under-performing sites.
A statement issued to Admiral staff by the pubco's chairman Jonathan Paveley said that Andrew Mountain, operations director North and Christine Kershaw, operations director South, and their respective teams would report to Kevin Georgel, who has assumed the role of managing director for all operations and commercial teams.
A one-time head of Tattershall Castle Group and Innspired, Brook joined Admiral at the end of 2008 for a fixed two-year contract to head up a new division within the business "to address that part of the pub estate with the most trading and other challenges", Paveley said.
"In that time Peter and his team have materially improved the performance of the Phoenix estate commencing as a turnaround operation which following the business restructuring became a profit maximisation/disposal exercise.
"This has been a very tough challenge and we are much indebted to Peter for the successful achievement of the task and the energy, dedication and focus he has brought to the task."
Paveley said Brook "had indicated some time ago that he would not seek to extend his contract with Admiral and that, having made such headway at Phoenix, he would like to take on another challenge and in this we wish him well".
He added that Georgel, who moved to Admiral from Punch Taverns earlier this year, would be "focused on maintaining trading performance while extracting full value for any sites identified for sale".
Admiral Taverns went into a pre-pack administration earlier this year and is effectively owned by Lloyds Banking Group. Paveley was appointed chairman in November 2009.