The club will formally complete the loan signing of Huddersfield Town winger Rajiv van La Parra when the transfer window re-opens.
The 27-year-old finalised his move ahead of the re-opening of the transfer window when he will officially join the club until the end of the season.
The Dutchman brings a wealth of experience, having made almost 300 career appearances, including 40 during Huddersfield’s promotion season and a further 33 in the Premier League last term.
The player has made five Premier League appearances this campaign, his most recent coming at Burnley in October.
Boro boss Tony Pulis has made no secret that he wanted to add pace to the wide areas, and van La Parra was identified as a player with those qualities.
The player won’t be eligible for our New Year’s Day fixture with Derby County, due to registration deadlines in accordance with the re-opening of the transfer window.