Raphael Guerreiro confirmed he has a fracture in his leg and will miss the remainder of Portugal's Confederations Cup campaign.
The versatile Borussia Dortmund left-back assisted Cristiano Ronaldo's goal in Wednesday's 1-0 victory over Russia but was taken off on a stretcher in the second half.
Coach Fernando Santos said after the match he feared the 23-year-old had sustained a fracture, and his concerns have now been confirmed.
However, Guerreiro said the issue was pre-existing and he is not feeling any pain in the area that resulted in his withdrawal in Moscow.
"I have a fracture but it is more than three months old," he wrote in a now-deleted post on Instagram.
"Fortunately, I do not have any more fractures where I feel pain, but I can't put my foot on the ground or move it.
"I will remain here to support my team-mates for the rest of the competition."