The Namibia international departed Ewood Park upon the expiry of his contract at the end of June, despite the Lancashire outfit trying desperately to extend his deal.
Negotiations broke down between the two parties, allowing the 24-year-old to seek pastures new this summer.
Now, Nyambe is set to join Darragh Lenihan at the Riverside Stadium, as he has agreed a deal with Chris Wilder’s promotion chasers.
Nyambe has been an ever-present for Rovers for a number of years at right-back, appearing 31 times for the Lancashire outfit in the Championship last season, but has now chosen to pursue a new opportunity.
Boro are set to lose Djed Spence in a big-money move to Tottenham Hotspur in the coming weeks, so Nyambe will arrive as competition for exciting wide player Isaiah Jones at right wing-back.