A deal worth £2.5million, with the potential fee rising to £3.1m for he defender is set to be completed in he next two days.
According to the Express and Star, the centre back will be joining Garry Monks side, just a year after signing for Blues.
The 28-year-old made 45 appearances across all competitions, including 43 in the Championship. However, he didn’t feature in Saturday’s defeat to Ipswich and was not a part of last night’s Carabao Cup squad against Crawley Town – to prevent him from being cup tied.
Shotton is thought to be a replacement for Ben Gibson, although a second bid of £20million from West Brom was rejected.
Despite their opening day defeat to Wolves, Boro are still the favourites for promotion. It’s not clear the arrival of Shotton would free up Gibson’s move though.