Boro have completed the signing of Ravel Morrison on loan until the end of the season.
The midfielder, 26, spent the first half of the campaign with Premier League club Sheffield United, where he made four appearances.
Morrison, who began his career as a youngster with Manchester United, brings a wealth of experience to the club despite his young age.
A varied career has taken the player to West Ham United as well as Birmingham City, Queens Park Rangers and Cardiff City on loan, while he has also spent time abroad with Lazio, Mexican side Atlas and Swedish outfit Ostersund.
Head coach Jonathan Woodgate said: “Ravel is a terrific signing for us. He is a real quality player with plenty of experience, and will give us something different to what we have.
“He has a desire to do well and succeed, and that attitude fits in with in well with our ethos here. I met him this week, we had a really good talk, and I think he we will be really good addition to our squad.”