Aleksandar Mitrovic has been stretchered off early in this afternoon's FA Cup tie against Birmingham City.
The striker was hurt in the build-up to Newcastle United's opening goal, which was scored by Daryl Murphy after a goalmouth scramble.
Mitrovic appeared to suffer a knee injury in a collision with Birmingham goalkeeper Adam Legzdins.
The 22-year-old – who had been handed a rare start by Rafa Benitez in the third-round tie – was given oxygen as he was stretchered off.
And there were chants of "Mitro, Mitro, Mitro" from Newcastle's 4,600-strong travelling support at St Andrew's as he was taken off the field by medics.
Mitrovic was replaced by Yoan Gouffran in the 10th minute.
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