Newcastle centre-back Steven Taylor is facing the rest of the season on the sidelines after injuring his achilles tendon in the defeat against Chelsea on Saturday.
The 25-year-old joined centre-back partner Fabricio Coloccini in coming off during the game and Newcastle's seemingly impenetrable defence from the start of the season now looks frail.
A club spokesman said: "After medical assessment, [Steven] will be having surgery on Monday.
"It is likely he will be out for the rest of the season."
The injuries to Taylor and Coloccini mean that summer signing Davide Santon, who has been unable to gain any minutes so far this season, is likely to have a run in the team, with Danny Simpson and James Perch expected to move into central positions.