Sega-owned Sports Interactive initially invited ten agencies for a full-scale pitch. It has hired 77 for a six-month brief.
It is understood 77 made it through to a final round that involved a three-way shoot-out.
Of 77's decision to participate in a process previously labelled 'extraordinary' by one PRWeek source, MD Nadia Gabbie said: 'No one forces you to pitch.'
Its work will be led by director James Hoyle, who will report to Sports Interactive head of PR Ciaran Brennan.
The brief was previously reported as being worth £60,000, with 77 working alongside both Sega and Sports Interactive's press office functions.
Gabbie said the focus would be on media relations: 'It's keeping the franchise front of mind in a crowded marketplace.'
Football Manager 2014 is expected to launch in the autumn. Last year's brief was handled by Lexis, which is thought to have not repitched for the work.