Adam Pearson has already revealed that the club are aiming to have a squad of 20 or 21 senior professionals competing for first team places. City have 18 senior players under contract beyond this summer, while the likes of Danny Coles, Sam Collins, Ryan France and Ray Parlour are out of contract.
Brown suggests that there may be four or five players incoming and outgoing.
Darryl Duffy is one player expected to leave, having expressed an interest in staying at Swansea, where he ended the season on loan. Hartlepool, another team the Scottish forward spent a successful loan spell with, are among a number of other teams also ready to make an offer.
Michael Bridges and Jon Parkin could also be on their ways out having failed to establish themselves in Brown's plans, while Dean Windass is set to join from Bradford on a permanent basis.