The merger has been recommended for referral to the commission by Patricia Hewitt, trade and industry secretary, and the companies are expected to face stiff opposition to the deal.
Most of the objections are likely to be concerned with its share of advertising, which will be above 50% if the two companies combined.
Bridgeman will be well placed to help Granada make the best case possible in support of the merger. Before he left the OFT in 2000, he oversaw the investigation into Carlton's unsuccessful acquisition of the ITV assets of United News & Media, now United Business Media.
It was eventually beaten to the assets -- including Meridian and Anglia TV -- by Granada, which paid £1.7bn for them.
Bridgeman, who is head of the regulatory division at City PR firm Cardew Chancery, is understood to have been working with Granada since the summer. Bridgeman joined Cardew in July from Omnicom-owned public affairs agency GPC, which he moved to when he left the OFT.
If you have an opinion on this or any other issue raised on Brand Republic, join the debate in the .