Portugal boss Robert Martinez expressed concerns about players' security after several spectators got onto the pitch to seek a selfie with Cristiano Ronaldo during and immediately after Portugal's 3-0 win over Turkey in Dortmund on Saturday.
Portugal captain Ronaldo posed for a selfie with a young boy with around 20 minutes left to play, but five others later made it on to the pitch in an apparent attempt to take a picture with a visibly unhappy Ronaldo.
Man of the match Bernardo Silva brushed off the incidents, saying it was "the price we pay for being so recognised in the world of football and having a player like him (Ronaldo) with us".
Martinez, however, said the pitch invasions left the players exposed and should have been prevented by security staff.
"It's a concern because today we were lucky that the intentions of the fans were good," he told reporters.
"I think we all love a fan that recognises that big star and the big icons ... but you can understand that there is a very, very difficult moment if those intentions are wrong."