Sunderland and Bolton have both made enquiries for Peterborough captain Jack Baldwin, according to Sky sources.
The two relegated sides are competing for the 24-year-old centre-back, who is valued at £250,000.
The Black Cats need to sell before they make an official offer however, with Bolton hoping to take advantage and tie up a deal for the defender next week.
Sunderland, meanwhile, are also in talks to sign free agent Lyle Taylor following his release by AFC Wimbledon.
The striker is also of interested to Charlton, Southend and Peterborough, however.
New Sunderland manager Jack Ross wants to bring in at least two strikers to the Stadium of Light this summer.
Source: Skysports