The 22-year-old has backed his Marseille team-mate after he was criticised for comparing the Brazil and Santos star's recent performance against Russia to "cat p***"
The 30-year-old was highly critical of the Santos starlet's performance in the recent friendly against Russia, tweeting: "Neymar is the Justin Bieber of football. Brilliant on the old YouTube. Cat piss in reality..."
However, Mendes has insisted people should not judge the controversial QPR loanee, revealing that the pair have become close during his spell in France.
"I first tried to know the person and not to draw conclusions from what I have read," Lucas told O'Globo.
"We are trying to discuss, play a little, but there is a language barrier. We arrived at the club at the same time we tried to help each other.
"It is clear that we do not take all the reactions and attitudes he may have, but so far he is very liked by the group. The group loves [him].
"Sometimes he is a bit harsh in training, and he doesn't like it if we complain. But it is how he is and it is not so bad. He never wants to lose, sometimes he goes crazy."