Summer speculation had linked the Spain international with a move to Barcelona, and he has since struggled to earn a regular place in the Reds' first team.
Riera held talks with Benitez regarding his role at Liverpool after only being named a substitute in the defeat at Tottenham at the start of the Premier League season.
The former Espanyol star admits he is unhappy at being left out of the starting XI and that he rowed with his boss, but he insists the incident is nothing personal.
"I didn't play the first game because I started training late after the Confederations Cup, like Pepe Reina and Fernando Torres," said Riera.
"I was angry and had a flare-up at Benitez, but the day I don't get angry for being a substitute I will retire."
Despite the bust-up, Riera insists he has nothing but respect for his manager.
"Benitez is a special coach who defends his own. I know he is with me, because he said so," he added.