Portugal coach Fernando Santos is deeply disturbed by Danilo Pereira's unexplained injury.

"Pereira was fractured on the right rib ( ribs) during Saturday training. He was considered unable to play," The Portuguese Football Federation (FPF) officially announced.

Danilo Pereira, who plays for Paris Saint-Germain (PSG), has been selected in the first game and helped the team secure victory by playing full-time.

"It's an injury that no one can explain. I can't understand how that could have happened. I haven't seen how the injury occurred. I didn't think it was serious for the first time,” Santos said.

"We did some tests to make sure Pereira was breathing properly, and later we found that the injury was serious. I can't talk in detail because I'm not a doctor, but there are three other players who can replace him. We are very sad because of Pereira. He had very positive energy and was convinced that it would bring us good energy,"