"This is a disgrace", Neymar wrote on Instagram shortly after the match.
UEFA are investigating PSG striker Neymar, as first revealed by SPORT, for comments he made after Man United beat his side last week in the Champions League.
The 27-year-old Neymar was so reportedly enraged he had to be restrained by PSG staff to stop him entering their dressing room.More news: Lilly Singh Will Take Over Carson Daly's Late-Night Slot on NBC
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It is understood that UEFA are furious by Neymar's behaviour and have now announced that the 27-year-old is under investigation for his outburst.
UEFA, on Wednesday, said a disciplinary investigation has started after the PSG forward criticised in an Instagram post the officiating of the defeat to Manchester United.
Neymar, who did not play in the fixture due to his current foot injury, voiced his opinion on social media after the match.
"And UEFA still pick four guys who know nothing about football to review the VAR decision in slow motion. that handball simply doesn't exist!"