Pearson was promoted from executive director to managing director of MG OMD in July this year. He has been at the agency for 16 years, starting at the Omnicom media agency as a planner/buyer.
Following Pearson’s elevation, MG OMD has promoted Natalie Bell, the executive director, digital, content and experience, to managing director after eight years running the agency’s digital team.
Ffitch, who was managing director of MG OMD for seven years before becoming chief executive in April 2013, is leaving MG OMD after 25 years to join Telegraph Media Group as director of advertising revenue.
Philippa Brown, the UK chief executive of Omnicom Media Group, said: "I would like to thank Robert for all he has given MG OMD over such a long period of time and also to thank him for having established such a strong team that I am able to announce two well deserved promotions today from within the agency’s own ranks.
"Tim is a leader of distinction with a great client pedigree, huge vision and an exceptional team already in place to write the next chapter in MG OMD’s history."