Platt is understood to be up against his second in command, Gary Digby, as well as Granada sales managing director, Simon Pardon, to take on the role of sales director at the merged ITV sales house.
Duff, who is currently chief executive of Granada Enterprises, beat his opposite number at Carlton Sales, Martin Bowley, to the top sales post at the merged ITV earlier this month. He is believed to be interviewing the three candidates today.
Duff will take the weekend to mull over his decision with an announcement expected Monday or Tuesday, according to a Granada spokeswoman. Duff was unavailable for comment at the time of writing.
In earlier reports Carlton's Digby has been named the favourite for the job. His appointment would ease criticisms that the management of the new ITV is being dominated by Granada men.
The shortlist was drawn up by executive headhunting firm Heidrick & Struggles to help select the best people from both Carlton and Granada for the positions on offer. Duff is said to have specified that he would only consider internal candidates, according to the spokeswoman.
The ITV sales director will report to Duff, who will lead negotiations with agencies over ITV's share of next year's ad budgets, following the introduction of the Contract Rights Renewal system, and oversee the integration of the two sales houses.
Duff is also recruiting a cinema director, a head of knowledge management, a marketing director and an operations director.
The merger of the two operations is expected to result in as many as 300 redundancies.
Last week Ofcom announced that former Starcom Motive chief executive David Connolly had been appointed to take on the role of ITV adjudicator, to rule over disputes arising between advertisers and ITV's combined sales house.
The merged ITV sales house is set to be created on December 1 and will control a 52% share of the £3.6bn UK TV ad market.
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