SON HEUNG-MIN has been forced off with injury in the first half against Marseille.
The Tottenham forward looked groggy as he was helped off the pitch following a collision with Chancel Mbemba.
Son received treatment on the pitch for a few minutes as a concerned Alexis Sanchez watched on.
But he was unable to continue as the South Korean appeared to be suffering from a concussion.
The incident occurred as Son challenged Mbemba for a header – but came off second best.