Portugal captain Cristiano Ronaldo has been forced out of his side's Nations League match against Croatia with a toe infection that his manager Fernando Santos has likened to a bee sting.
Speaking at a news conference, Santos said the 35-year-old noticed the problem at Wednesday's training session.
"He had been training well, then suddenly on Wednesday one of his toes was red as if he'd been stung by a bee," Santos said.
"Now we have to wait. With an infection, you don't know how long the recovery is going to take."
Ronaldo's absence on Saturday means he will not have the chance to become only the second men's player to ever reach 100 international goals.
The Juventus star is currently on 99 goals and is looking to reach former Iran striker Ali Daei, who holds the men's record with 109 goals.
Portugal are looking to defend their Nations League title, having won the inaugural competition last year when they defeated the Netherlands 1-0 in the final.
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