Goalkeeper Tomas Mejias has rejoined Boro on a free transfer, subject to international clearance.
The Spanish stopper, 30, signs a 2-year deal to return to Teesside.
A graduate of Real Madrid’s youth academy, Mejias made 17 appearances for Boro between 2014 and 2018.
A regular understudy to Dimi Konstantopoulos, Victor Valdes and latterly Darren Randolph, Mejias’ most memorable moments in a Boro shirt came in away victories over Manchester City and Manchester United in the FA Cup and League Cup respectively.
He is a familiar face to both head coach Jonathan Woodgate, his one-time captain at Boro, and Leo Percovich who was goalkeeping coach during Mejias’ first stint with the club.
Mejias returns after a single season in Cyprus, where he featured 28 times for Omonia Nicosia in the top flight.