Portugal defender Pepe missed a training session on Monday as a precaution after suffering a problem with his thigh, a team spokesman told reporters.
"Pepe has a muscle pain in his thigh and is not going to train today as a precaution," the spokesman said.
The 33-year-old Brazilian-born defender has had an excellent tournament and his absence from Wednesday's Euro 2016 semi-final against Wales would be a significant blow.
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