Manchester United defender Craig Cathcart will spend the rest of the season on loan at Plymouth Argyle.
Cathcart linked up with the Championship club in August and has become a key figure in Paul Sturrock's side.
The teenager has made 17 appearances for the Pilgrims in all competitions, scoring once against Ipswich Town.
Sturrock had been keen to hang on to Cathcart and the club have confirmed United have agreed to an extension.
The paperwork is set to be completed after Christmas and Cathcart is in line to start Boxing Day's game against Southampton.