Sunderland could face a battle to keep hold of goalkeeper Jordan Pickford in January as Everton are reported to be lining up a move.
Blues boss Ronald Koeman is keen to sign a young goalkeeper to put pressure on, and eventually replace Maarten Stekelenburg, and Pickford is said to be his top target.
The Black Cats stopper is one of the best young goalkeepers around and his stock has risen even further after he was called up into the England squad last week to replace the injured Tom Heaton.
Sunderland will fight to keep hold of Pickford though with reports claiming they are ready to offer him a bumper new deal to fight off interest from Everton and other clubs who are showing an interest.
Manchester United have also shown an interest in the past and Sunderland are bracing themselves for offers when the January transfer window re-opens.