Blues release trio
The trio are being allowed to leave on Bosman free transfers, as Bruce believes they will not be capable of handling life in The Premiership.
Striker Adebola has failed to recapture his form after a year-long lay-off with a knee injury, and failed to shine during a loan spell at Oldham, who play two rungs below the top-flight.
Former York City winger McCarthy has been plagued by injuries during his career, and Bruce feels he would struggle in The Premiership.
Sonner has found life equally difficult under Bruce, and it came as no great surprise when he was told his contract would not be renewed.
With places available, Bruce is set to meet with the board to discuss possible transfer targets.