Cobbold, who joins in the summer, will report directly to Bailey. He will focus on strategic and business development, as well as having operational responsibility for the group's sports division, magazine and exhibitions, and Voice Media.
The appointment comes as Bailey begins to change the way the company is run. In hiring Cobbold, she brings in-house the kind of expertise that the previous management relied on consultancies such as McKinsey for.
Bailey has shaken up her senior team since she joined the company in February, stripping out the level of managment between herself and Trinity's national newspapers, including the Daily Mirror, Sunday Mirror and The People.
Last week saw the departure of Alisdair Luxmoore, marketing director of the national titles. He follows national newspapers managing director Mark Haysom and corporate development director Richard Wyatt out the door, which has been revolving since Bailey's appointment was announced.
The most high-profile departure is that of Joe Sinyor, the group's chief executive of newspapers, who quit in January.
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