Middlesbrough have signed Dan Barlaser from Rotherham on a deal that could rise to £1.5million.
The midfielder, who has played for both Turkey and England at youth level, has agreed to join on a three-and-a-half-year contract.
The club announced the signing on social media on Sunday morning in the wake of their 2-0 victory against Watford in the Championship yesterday.
The win against the Hornets pushed Michael Carrick's side back into third place in the second tier, with only five points separating them and 11th place side Preston in the table.
Ahead of what promises to be a very competitive race for the playoffs, Middlesbrough will hope the central midfielder can help steer them back into the Premier League.
Barlaser has chalked up 30 appearances in all competitions for Rotherham so far this season, netting twice and providing seven assists.
The 26-year-old's Boro debut could well come as early as Saturday next week, when Carrick's side face Blackpool at the Riverside Stadium.
Middlesbrough signed Cameron Archer on loan from Aston Villa earlier this month, with the striker recording his first assist for the club during his first start against Watford.