Manchester United winger Antony was seen leaving the stadium on crutches after he was was stretchered off the pitch during Thursday's 1-1 draw with Fenerbahce.
The Red Devils made it three draws from three games in this season's Europa League as they shared the points with the Turkish side managed by former boss Jose Mourinho.
Christian Eriksen brilliantly finished off a fine team move to open the scoring in the 15th minute but the hosts hit back through Youssef En-Nesyri shortly after half-time.
Erik ten Hag brought on Antony in the 73rd minute in the hope that the Brazilian could help his side find a winner.
However, his cameo lasted just 16 minutes as he signaled to the bench that he needed to come off due to an injury of some sort.
Antony was seen leaving the Fenerbahce stadium on crutches after Thursday's 1-1 draw
The problem seemed relatively innocuous at first but Antony then fell to the turf and a stretcher was needed to remove him.
And the seriousness of the injury was made clear as the 24-year-old was pictured leaving the ground on crutches while wearing a protective boot.
Thursday's result leaves United 21st in the 32-team Europa League table.
Only goal difference is keeping Ten Hag's men out of the automatic elimination spots and the pressure on the Dutch manager is showing no signs of easing up.