The Queens Park Rangers man, who is currently on a season-long loan with Olympique de Marseille in France, was less than impressed with Brazil starlet Neymar during the 1-1 draw in the friendly against Russia at Stamford Bridge on Monday night.
Barton took to his social networking site to compare the 21-year-old to pop star Justin Bieber and make a further less savoury comment on the Santos player's display.
It is debatable whether Neymar will be too concerned with Barton's thoughts, but the playmaker and Barton have form in this area after the Liverpool-born midfielder aired his opinion on the Santos man last month.
Responding to criticism of him by Barton, Neymar, who has been strongly linked with a move to Barcelona (via Sky Sports), claimed he had never heard of the QPR man.
This clearly annoyed the 30-year-old, as The Metro reported.
Neymar has not yet replied to Barton's latest outburst, but we are not expecting too much in response.