It was at the end of the first half that the national team's right-back Emil Krafth unfortunately fell in a duel with Tranmere Rovers' Ethan Bristow.
He grabbed his left knee right away and couldn't get up on his own.
He was carried off on a stretcher and replaced by England international star Kieran Trippier.
The match between Newcastle and League Two team Tranmere is in the second round of the English League Cup.
The match is in progress.