Newcastle United's Isaac Hayden is having surgery on his ankle.
The midfielder, named on the bench at Carrow Road on Tuesday night, has been troubled by a niggle problem in recent weeks.
And Hayden is having an operation today on his ankle which could sideline him for four weeks.
United manager Rafa Benitez said: "He needed an operation. It's not very serious."
Asked how long he could be out for, Benitez said: "It could be four weeks – or less."
Hayden – who joined Newcastle from Arsenal last summer – has been a regular for United this season.
Championship leaders Newcastle take on Aston Villa at St James's Park on Monday night.
More to follow