Northampton Town release defender Gabriel Zakuani after contract talks broke down over his international commitments.
Mansfield continue their rebuilding for the new season by signing experienced former Northampton centre-back Zander Diamond.
Midfielder Shaun Whalley signs a new two-year contract with League One side Shrewsbury Town.
Shrewsbury winger Shaun Whalley has signed a new contract with the club.
Teenagers Hugo Logan and Sam Nombe have signed professional contracts at MK Dons.
Under-21 sides from Premier League clubs will continue to compete in the Checkatrade Trophy for the next two seasons.
League One and Two clubs vote in favour of retaining invited under-21 teams in the Checkatrade Trophy for two more seasons.
Partick Thistle midfielder Stevie Lawless would be surprised if manager Alan Archibald would be interested in a move to Swindon Town.