Atletico Madrid defender Robin Le Normand was diagnosed on Tuesday with a head injury after a collision in last weekend's La Liga derby draw against Real Madrid.
The centre-back, 27, sustained the injury late in Sunday's game as Atletico snatched a 1-1 draw against the visiting Spanish champions at the Metropolitano stadium.
"Le Normand suffered a heavy blow to the head in the final minutes of the Madrid derby, for which he has undergone a series of tests and an assessment by specialists who have determined that he has suffered a traumatic brain injury with subdural haematoma," said Atletico in a statement.
"In the process of our player's return to competition, the guidelines set out in the protocol established for this type of trauma will be followed."
The French defender was not included in Atletico's squad to face Benfica in the Champions League on Wednesday.
Le Normand, who won Euro 2024 with Spain in July, joined Atletico from Real Sociedad this summer and has become a regular starter for Diego Simeone's side.
