Sweden midfielder Kristoffer Olsson is suffering from multiple small blood clots on both sides of his brain as a result of an extremely rare inflammatory condition in his brain vessels, the player's club, FC Midtjylland, said Thursday.
Olsson, 28, has been in hospital and was put on a ventilator after falling unconscious at home last month. He was admitted to Aarhus University Hospital where he had undergone several scans and tests in recent weeks, the club said.
"The diagnosis matches the thesis on which the medical specialists have so far worked and treated Kristoffer," the Danish club said in a statement.
"Kristoffer Olsson's condition is now considered stable and the doctors continue to see some progress. At the same time, they feel that Kristoffer's level of consciousness is increasing.
"In the coming period, the doctors will slowly try to phase the Swedish midfielder out of the ventilator. But he remains in intensive care and it is not yet possible to say anything about the treatment's time frame and final prognosis."
The club said last month that Olsson's condition was not related to self-harm or external factors.
Olsson, who has 47 caps for Sweden, started his senior career at Arsenal and has also played for Swedish side AIK and Belgium's Anderlecht.