The Portugal captain has had a miserable two games so far, and seemed to be showing the strain of his faltering performances when he reacted badly to a television reporter’s question by throwing his microphone into a nearby river.
The reporter had approached him to ask him about Portugal’s crunch match with Hungary on Wednesday.
The reporter said: “Ronaldo, are you prepared for this game today?”, to which the three-time Ballon d’Or winner said nothing, wrestled the microphone from his grasp and chucked it into the water.
The reporter is then quickly ushered away by the swathes of security surrounding the player.
Ronaldo’s displays have come under scrutiny after Portugal were held to a 1-1 draw by Iceland in their opening game, after which his comments about their opponents’ “small mentality” drew widespread criticism.
The Real Madrid superstar is yet to score at Euro 2016, and missed a penalty in Portugal’s second match, the goalless draw with Austria, a result which leaves Portugal third in Group F and in danger of exiting the tournament before the knockout stages.
They need a win against Hungary in Lyon on Wednesday night to guarantee a place in the last 16.
His team-mate at club level, Gareth Bale, meanwhile, has begun his first major tournament in extremely impressive fashion. He is joint-top of the goal-scoring charts with three goals, alongside Alvaro Morata.