Sunderland goalkeeper Jordan Pickford is facing up to two months on the sidelines with a strained knee ligament.
The 22-year-old, who has been in terrific form since breaking into the first team this season, suffered the injury during Sunderland's 3-1 defeat to Manchester United on Boxing Day.
Pickford played the full 90 minutes at Old Trafford, but did not feel the injury until after the match. He is thought to have suffered it in a collision with team-mate Papy Djilobodji as Zlatan Ibrahimovic chipped him to score United's second goal.
"Jordan has good news and bad news. The good news is he hasn't ruptured his ACL, the bad news is he's strained it," Sunderland boss David Moyes said.
"We're looking at six to eight weeks, it's a major disappointment for him and for us because he's been saving us points."
Sunderland travel to Burnley on New Year's Eve, with Vito Mannone set to replace Pickford in goal.
The Italian started the season as David Moyes' No 1 but fractured his elbow in August, opening the door for Pickford to stake his claim in impressive fashion.
Moyes added: "Vito is fine and he's been training for many weeks since his injury. He has a lot of experience."
Pickford has become a full England squad member under Gareth Southgate and has been linked with a move away from the Stadium of Light in the national press.
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