By Patrick Haond
Last Updated: 01/01/70 1:00am
The 31-year-old became unsettled after the arrival of coach Laszlo Boloni (pictured), and feels he was treated unfairly by his former side.
Wolves had a look at the Frenchman on trial, before he found another club in Le Championnat.
"Considering what I gave to Stade Rennais, I deserved a little respect," he complained.
"I was always there during difficult moments and there were some of those!
"I tried to help the young players. I never caused any trouble. I never cheat, and they made me pay for that.
"They banned me from the squad, even from the changing room. I still can't understand the reasons.
"I talked with the coach and he told me he will watch, oversee, but I never got a chance.
"The coach knew he would not rely on me for a while. Last week, they even prevented me from playing with the reserves.
"I was shocked by the way I was treated."
Echouafni is pleased with the move to Nice, and feels a lot of his unhappiness will fade.
"I am released," he exclaimed. "I had five very difficult weeks - even nightmarish.
"I am very, very happy. I find again a squad, a coach and a club that trusts me at Nice."
Rennes hit back via general manager Pierre Dreossi.
"At the end of last season, I told his agent we would let him go free," he revealed.
"Despite that, he didn't find a new club in the summer.
"He talked about what he did for the club, but he only did his duty as a player, with good wages.
"I can understand Echouafni is a little angry not to enter into our plans anymore. But we have always been correct.
"And if, today, he is at Rennes, I believe he can thank Rennes."