Dani Alves is hoping Paris St Germain team-mate Neymar will have learned his lesson following his "hot reaction" in lashing out at a supporter after the club's Coupe de France final defeat to Rennes on Saturday.
Walking up the steps at the Stade de France to collect his loser's medal, social media footage shows Neymar being confronted by a fan with a mobile phone.
The Brazil striker initially pushes away the hand holding the phone, and after a few words are exchanged, he then raises his right arm to the chin of the man who flinches his head backwards.
Fellow Brazil star Alves, speaking to L'Equipe, said: "I think this is a very delicate moment because this event happened after a heavy defeat.
"It was a hot reaction, but misplaced and that should not have happened. But it will serve as a lesson for him to progress as a man.
"'Ney' is an exceptional young man but there are times when he loses his temper.
"Despite our friendship, I do not approve of his gesture. But I think he understood the lesson and it will not happen again."
After the incident, Neymar initially conceded in an Instagram post he later deleted that he reacted badly, but added: "No-one can remain indifferent in defeat."
In a subsequent Instagram post, he wrote: "Nobody likes to lose, so I ... who knows me knows how competitive I am and how much defeat shakes me.
"But losing is part of an athlete's life, makes us grow, makes us think, makes us BETTER."
PSG boss Thomas Tuchel made his feelings clear about Neymar's actions during Monday's press conference to preview last night's 3-2 Ligue 1 loss at Montpellier.
Tuchel said: "I do not like it. You cannot do that. It is simply not possible to do it.
"It was not easy going up to collect the medals after the defeat. It was difficult for me, as well as everybody else. However, we have to accept it. If we win, it is easier. In defeat, you must show respect – always.
"You simply cannot get into conflict with a spectator."
Last week, Neymar was banned by UEFA for PSG's opening three Champions League group matches for next season after being found guilty of "insulting match officials" in another Instagram post following the round-of-16 second-leg defeat to Manchester United at the Parc des Princes on March 6.
For the clash with the fan, French league officials could now hand Neymar a domestic ban it has been suggested could see him miss up to eight matches.
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