The 34-year-old striker has signed a two-and-a-half year contract with the Argentine club after less than six months with Emirati club Baniyas.
"This happened after my negative experience in Arabian football," Trezeguet told a press conference. "Throghout my career, football has always made me see things differently.
"When the opportunity to come here appeared, I did not think twice. Football is passion and I could not live that in Arabian football.
"Playing at River is a unique experience for any player. This will be an enriching and important experience. I am well aware of where I am.
"I think I can live the best moments of my career here."
River Plate sit second in Nacional B, two points behind Instituto, and Trezeguet is confident that his side can return to the top tier of Argentine football.
"My goal is the same as everyone else's... We want to secure promotion as quickly as possible," he added.
"This is the beginning of an adventure that I hope will end in the best possible way. This will be a new experience in every way.
"I am really eager to start right away."
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