Callum Roberts left the Stadium of Light on crutches – after scoring a stunning free-kick against Sunderland.
Newcastle United's Under-23s booked a place in the Premier League International Cup semi-finals last night.
The club beat Sunderland 11-10 on penalties after drawing 2-2 after extra-time.
First-team manager Rafa Benitez tweeted: "Congratulations to our NUFC U23. Great job, great result and great achievement for the lads and all the staff. Good luck for the next games."
North Shields-born Roberts, 20, had scored an injury-time goal to take the game into extra-time.
However, the winger was taken off in the 104th minute after twisting his ankle. The 20-year-old, wearing a protective boot, left the stadium on crutches. He will be assessed today by the club's medical team.
Coach Ben Dawson said: "I think he's just went over on his ankle. He just twisted his ankle a little bit and went down. We'll check."
Newcastle defender Curtis Good opened the scoring in the 28th minute, but Lynden Gooch equalised before the break.
Gooch put Sunderland ahead in the second half, but Roberts beat Max Stryjek from almost 30 yards to equalise.
Roberts tweeted: "Eventful night but buzzing to be in the semi final, lads were excellent."
Click on the video above for a gallery of images from Newcastle's Premier League International Cup win over Sunderland