Tottenham Hotspur defender Jan Vertonghen was substituted during the first half of the Champions League semi-final first leg against Ajax after sustaining a nasty head injury.
Vertonghen was left with blood pouring from his face following a clash between himself, teammate Toby Alderweireld and Ajax goalkeeper Andre Onana.
The 32-year-old was treated by medical staff on the pitch before attempting to carry on, however, he only lasted a few seconds and was eventually helped down the tunnel by club doctors.
The manner of Vertonghen's departure from the pitch will raise concerns after the medical team allowed him to re-enter the field of play, despite being unsteady on his feet and displaying symptoms of concussion.
He was subsequently helped from the field after appearing to almost faint, with Vertonghen then undergoing further examinations from club doctors back in Tottenham's changing room.
The injury occurred when Vertonghen, along with centre back partner Alderweireld, attempted to get on the end of a Spurs free kick and the former was caught in the face by Ajax's Onana, who was looking to punch the ball clear.
Both Tottenham defenders were left on the floor in the aftermath of the incident, however Alderweireld was able to carry on having taken a knock to his hip.
Vertongthen's departure came at the worst possible time for Spurs, with Mauricio Pochettino's side trailing at half-time after an early goal from Ajax midfielder Donny Van De Beek,
The Spurs players were looking to get back into the game after falling behind to a Donny van de Beek goal, who ironically has been recently linked with a move to the Tottenham Hotspur Stadium.