The Brazil international, who joined the club last summer for a €222 million world-record fee from Barcelona, was not present as PSG dispatched their nearest rivals with clinical efficiency, winning the Ligue 1 title in the process.
Dugarry has subsequently launched a scathing attack on the forward, who is currently recovering from ankle surgery , insisting he cannot be termed a "leader" if he is not there for his team's triumphs.
"How can Neymar not be there for the title game, how can we give him the label of leader when he does not come to share that?" asked Dugarry, who played for the likes of Barcelona, Bordeaux and Marseille, on RMC Sport radio .
"How can PSG accept something like that? How can he look at his team-mates in the eyes by behaving like that?
"He is spitting on the club. I think it's barbaric."
Neymar's season at PSG has been something of a topsy-turvy one; he has scored a total of 29 goals in all competitions, but the club were eliminated from the Champions League by Real Madrid, and rumours surrounding his future continue to swirl.
It has been suggested that Neymar could move to Real this summer, having circumvented any transfer that would involve him moving from Barcelona to their eternal rivals.
And Dugarry believes that Neymar would have shown more respect for a league title win had he still been in Spain, adding that the player's mentality sums up what is holding the club back in European competition.
"If he were at Barca, he would have returned without any problem," said Dugarry. "If I was a PSG player I'd be raging.
"I can't stand these players who are constantly navel gazing.
"This is a team sport, and it is the collective that win games, not individuals. If we think that PSG can win the Champions League with attitudes like this, we're having a laugh."