Former Blues loanee Richard Chaplow has joined League One Doncaster Rovers on a two-year deal, having been released by Millwall at the end of last season.
The 30-year-old joined Town after a short trial in February and went on to make three starts and three sub appearances. His only goal was the dramatic last-gasp winner at Watford in March.
The former England U21 international was amongst the players not offered a contract at the end of the season but who manager Mick McCarthy wasn't ruling out offering terms later on in the summer.
Elsewhere, former Blues winger Jordan Adekunle is back training with his old club Crawley Town.
The 19-year-old joined Town from Crawley in the summer of 2013 having impressed in a pre-season friendly and then a trial. He was released at the end of 2013/14 without breaking into the first team.