Hospital scans have revealed Liverpool goalkeeper Loris Karius sustained a concussion during the Champions League final defeat to Real Madrid, during which he made two crucial errors.
Massachusetts General Hospital have confirmed the German underwent assessments by Dr Ross Zafonte and Dr Lenore Herget at MGH and Spaulding Rehabilitation Hospital on May 31, five days after the 3-1 loss in Kiev.
Karius was on holiday in the United States but Liverpool's medical staff wanted him to be checked out and a subsequent examination found evidence of concussion, which doctors say could have affected his performance.
The goalkeeper was caught in the head by Sergio Ramos at a corner before Madrid's opening goal, which was the first to be blamed on Karius.
"With Mr Karius's permission we are providing information about his medical situation in an effort to prevent, where possible, the dissemination of incomplete or erroneous information," said a statement from MGH.
"On May 31 2018 Mr Karius underwent a comprehensive examination by Dr Ross Zafonte and Dr Lenore Herget.
"After carefully reviewing game film and integrating a detailed history - including his reported present and immediate post-contact subjective symptoms - physical examination and objective metrics, we have concluded that Mr Karius sustained a concussion during the match on May 26 2018.
"At the time of our evaluation, Mr Karius's principal residual symptoms and objective signs suggested that visual spatial dysfunction existed and likely occurred immediately following the event.
"Additional symptomatic and objectively noted areas of dysfunction also persisted. It could be possible that such deficits would affect performance."