Cesar was signed by the Nerazzurri in 2005 but immediately sent on loan to Chievo where he played second fiddle to Marchegiani for a season.
"Have you seen Inter and Brazil's goalkeeper?" Marchegiani said in an interview with La Gazzetta dello Sport. "He was my reserve.
"We knew that we were in competition for the same place. Inter were not able to play him straight away so they sent him to Chievo to acclimatise.
"And I have to say it would have been cruel and counterproductive to throw him in during a relegation dogfight."
Cesar did not play a single game for Chievo as they fought for survival in Serie A. He returned to Inter the following year.
"We knew that he had won the Copa America as a regular for Brazil and soon understood his qualities," Marchegiani explained. "He himself took into account that it was probably best to have a 'soft' experience with us and study our championship.
"He trained as if he were starting every Sunday," Marchegiani added. "I remember what struck me was his mental strength and the determination with which he went about achieving his objective of becoming Inter's No 1.
"He did that in a brief period of time. With all due to respect to Francesco Toldo, I thought it would take the Brazilian a bit more time."