Primesight management has confirmed it will be making a bid for the outdoor business.
SMG has an estimated debt forecast before disposals of £170m by the end of the year.
The firm presented its plans to the City last week at the end of a 100-day business review. They include selling off its non-core assets and restructuring its TV business. According to an SMG spokesman, Virgin Radio, Primesight and Pearl & Dean are worth £70m to £80m each.
SMG's senior management will be cut from seven to three "to ensure clear lines of accountability".
Rob Woodward, chief executive of SMG, said: "We have had a thorough look at the business and taken some short-term remedial actions to deliver sustainable growth."
Recent reports have also linked Richard Branson and former ITV chief Charles Allen to a bid for Virgin Radio.